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1.

Background

The aim of this study was to compare the external apical root resorption (EARR) in patients receiving fixed orthodontic treatment with self-ligating or conventional brackets.

Methods

Studies comparing the EARR between orthodontic patients using self-ligating or conventional brackets were identified through electronic search in databases including CENTRAL, PubMed, EMBASE, China National Knowledge Infrastructure (CNKI) and SIGLE, and manual search in relevant journals and reference lists of the included studies until Apr 2016. The extraction of data and risk of bias evaluation were conducted by two investigators independently. The original outcome underwent statistical pooling by using Review Manager 5.

Results

Seven studies were included in the systematic review, out of which, five studies were statistically pooled in meta-analysis. The value of EARR of maxillary central incisors in the self-ligating bracket group was significantly lower than that in the conventional bracket group (SMD ?0.31; 95% CI: ?0.60–?0.01). No significant differences in other incisors were observed between self?ligating and conventional brackets.

Conclusions

Current evidences suggest self-ligating brackets do not outperform conventional brackets in reducing the EARR in maxillary lateral incisors, mandible central incisors and mandible lateral incisors. However, self-ligating brackets appear to have an advantage in protecting maxillary central incisor from EARR, which still needs to be confirmed by more high-quality studies.
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2.

Objectives

The purpose of the present study was to radiographically evaluate the prevalence and characteristics of palatogingival grooves (PGs) in maxillary anterior teeth on cone-beam computed tomography (CBCT) to better understand the nature of these defects.

Methods

The CBCT examinations of 993 teeth (330 canines, 315 lateral incisors, 348 central incisors) in 191 patients (87 males, 104 females; age range 16–80 years) were evaluated retrospectively. The diagnosis and radiographic condition of PGs were obtained by consensus among all observers. Verification of PGs was achieved from the patients’ clinical records, which were stored in a database after their clinical evaluation. Differences in age, sex, occurrence, and location were evaluated by the Chi-square test. The level of significance was set at p < 0.05.

Results

Among the 993 teeth examined, nine PGs were observed in seven lateral incisors and two central incisors in eight patients (four males and four females). There was one bilateral case in the lateral incisors. The frequencies of PG occurrence and affected patients were 0.90 and 4.18%, respectively, without significance for sex and location (p > 0.05).

Conclusions

PGs were a relatively infrequent anomaly of teeth in this population, but when present, clinicians should understand the clinical features of these root variations.
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3.

Objectives

The aim of this study was to evaluate the localization, angulation, and resorption features of maxillary impacted canines on cone-beam computed tomography (CBCT).

Methods

This retrospective study examined the CBCT scans of 140 maxillary impacted canines in 102 patients (43 males, 59 females; mean age: 16.25 ± 6.31 years). The following impacted canine-related parameters were analyzed on the CBCT images: impaction side; location; root resorption levels of adjacent teeth; occlusal plane and midline distances of impacted canines; and angulations of impacted canines to midline, lateral incisor, and occlusal plane.

Results

Bilateral canine impaction was found in 38 subjects, and unilateral canine impaction was present in 64 subjects. Severe resorption was found in 14 canines. There were no significant differences between the occlusal plane and midline distances to the impacted canine cusp tip and root apex (p > 0.05). The midline angulation of right maxillary impacted canines was significantly higher than that of left maxillary impacted canines (p < 0.05), while the occlusal plane angulation of left maxillary impacted canines was significantly higher than that of right maxillary impacted canines (p < 0.05).

Conclusions

Maxillary canine impaction was more frequently seen in female subjects than in male subjects. Lateral incisors were more frequently affected than first premolars, and slight resorption was more frequently seen in adjacent teeth. CBCT assessment of maxillary impacted canines can provide accurate measurements of angular, linear, and resorption parameters.
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4.

Objective

This study aims to estimate the prevalence of congenitally missing lateral incisors in a sample of 2662 dental patients in Palestine.

Methods

A total of 2662 digital panoramic radiographs were retrospectively examined for the presence of congenitally missing permanent lateral incisors. The radiographs were obtained from the archival records of patients attending a local dental center at the city of Nablus in Palestine.

Results

The prevalence of missing lateral incisors among the examined population (n?=?2662) was found to be 1.91%. Unilateral agenesis accounted for 66.6% of the total cases that showed at least one missing lateral incisor. Around 79% of the unilateral cases were on the left side while 21% were on the right side. Bilateral agenesis accounted for 33.3% of 34 cases that had at least one congenitally missing permanent maxillary lateral incisor.

Conclusion

The prevalence of missing maxillary lateral incisors in this study population was 1.91%) which was within the range reported in different populations.  相似文献   

5.

Objective

The aim of this study was to evaluate and compare the craniofacial cephalometric morphologies among different cleft types in a Spanish population.

Methods

A retrospective cross-sectional study was carried out on 212 patients. The patients were subdivided into four groups according to their cleft types: unilateral cleft lip and palate; bilateral cleft lip and palate; cleft lip; and cleft palate. Angular and linear cephalometric measurements were taken on lateral radiographs.

Results

Unilateral cleft lip and palate was associated with a dolichofacial growth pattern, skeletal Class III with correct maxillary position, and lingual incisor inclination. Bilateral cleft lip and palate was associated with a mesofacial growth pattern, skeletal Class I with protruded maxillary position, and lingual incisor inclination. Cleft palate was associated with a mesofacial growth pattern, skeletal Class III with correct maxillary position, and lingual incisor inclination. Cleft lip was associated with a brachyfacial growth pattern, skeletal Class I with protruded maxillary position, lingual upper incisor inclination, and corrects lower incisor inclination. Significant correlations were observed between cleft types and their craniofacial cephalometric measurements.

Conclusions

The present information can be used for the determination of orthodontic treatment and even future orthognathic surgery planning, a requirement in most cleft patients.
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6.

Objectives

To determine the prevalence of odontogenic maxillary sinus pathologies and their relationship with periapical pathologies in the maxillary posterior teeth using cone-beam computed tomography (CBCT).

Method

Maxillary posterior CBCT scans of consecutive patients aged 20–77 years were evaluated retrospectively. Patients with at least one maxillary posterior tooth were included. Patients with edentulous maxillae or having one or more maxillary implants were excluded. Finally, 461 CBCT images were evaluated. Demographic data, such as age and sex, and pathologic findings of the right and left maxillary sinuses and adjacent teeth were recorded. Statistical analyses were performed using the Chi square test and binary logistic regression.

Results

The prevalence of right and left odontogenic maxillary sinusitis was 59.5 and 64 %, respectively. Maxillary sinus pathology was more common in males, and there was no relationship with age. Regarding the maxillary sinus pathology, 64 % had mucosal thickening, 19 % had partial opacification, 5 % had total opacification, and 12 % had polypoidal mucosal thickening. Right and left maxillary sinus pathologies were approximately twice as prevalent in patients with periapical pathology in at least one maxillary posterior tooth. Periapical pathologies in the right maxillary first molar and left maxillary first and second molars significantly increased the risk of maxillary sinus pathology with odds ratios of 2.53, 1.83, and 3.12, respectively.

Conclusions

Odontogenic maxillary sinus pathologies were present in >50 % of the study population. Periapical pathologies in the maxillary first and second molar teeth significantly increased maxillary sinus pathologies.
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7.

Purpose

Orthognathic surgery in reference to the maxilla attempts to correct underlying skeletal deformities and improve function. Consequently it has the potential to significantly alter the central esthetic unit of the face, the nasolabial region. In order to evaluate the nasal morphological changes which would result following anterior maxillary segmental osteotomy (superior and posterior repositioning); four angles namely, nasolabial, nasal tip projection, columellar labial and supra tip break angle were evaluated.

Method and materials

In ten selected subjects who have undergone anterior maxillary segmental osteotomy with superior and posterior repositioning, pre (T1) and post operative (T2) lateral cephalometric parameters pertaining to the four angles were analysed using Wilcoxon signed rank test.

Results

A significant increase in nasolabial angle and mild changes in nasal tip projection, columellar labial angle and supra tip break angle were observed.

Conclusion

The results of this study emphasize the need for the pre surgical evaluation of nasal morphology in every individual planned for anterior maxillary segmental osteotomy.
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8.

Purpose

Orthognathic surgery in reference to the maxilla attempts to correct underlying skeletal deformities and improve function. Consequently, it has the potential to significantly alter the central esthetic unit of the face, the nasolabial region. In order to evaluate the nasal morphological changes which would result following anterior maxillary segmental osteotomy (superior and posterior repositioning), four angles, namely nasolabial, nasal tip projection, columellar labial and supra tip break angle, were evaluated.

Method and Materials

In ten selected subjects who have undergone anterior maxillary segmental osteotomy with superior and posterior repositioning, preoperative (T1) and postoperative (T2) lateral cephalometric parameters pertaining to the four angles were analyzed using Wilcoxon’s signed-rank test.

Results

A significant increase in nasolabial angle and mild changes in nasal tip projection, columellar labial angle and supratip break angle were observed.

Conclusion

The results of this study emphasize the need for the presurgical evaluation of nasal morphology in every individual planned for anterior maxillary segmental osteotomy.
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9.

Introduction

Access osteotomies provide direct exposure to inaccessible areas of the deep part of craniofacial skeleton for treating pathologies involving vital structures. The use of maxillary swing approach for gaining wide access to the nasopharynx, infratemporal fossa, parapharyngeal space, middle fossa of skull base. Though the maxillary swing requires transfacial incision for wide exposure but with careful handling the scar is minimum and this approach can be used in young people.

Materials and Methods

Surgical resection is carried out following preoperative embolization of the involved feeder vessels. Total 16 cases were considered for this study.

Results

This article highlights cases successfully treated in our institution, the mention of complications associated with the cases along with management.

Conclusion

Maxillary swing is a good approach for getting access to the deep pathologies like JNA.
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10.

Objectives

To prospectively analyze the amount of alar flare, factors contributing to alar flare and efficacy of cinch suture as an adjunctive procedure for alar flare reduction.

Study Design

Thirty adult patients with vertical maxillary excess, who underwent Le Fort 1 impaction, were divided into 2 groups of 15 each. Alar cinch was performed as an adjunct procedure in group 2 patients and results were compared to group 1 which was the control group. Measurements were made on the patients and on 1:1 standardized photographs.

Results

Group 2 showed a near pre-operative alar position compared to group 1. The alar flare resulting from every millimeter of impaction was significantly less in group 2 compared to group 1.

Conclusion

Alar cinch suture restores the normal alar width by preventing the lateral drift of the naso-labial muscle and thereby reducing the postoperative nasal flare significantly.
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11.

Objectives

A novel, 3D technique to measure the differences in tooth crown morphology between the MSX1 cases and non-affected controls was designed to get a better understanding of dental phenotype-genotype associations.

Materials and methods

Eight Dutch subjects from a single family with tooth agenesis, all with an established nonsense mutation c.332 C > A, p. Ser 111 Stop in exon 1 of MSX1, were compared with unaffected controls regarding several aspects of tooth crown morphology of incisor and molar teeth. A novel method of quantitative three-dimensional analysis was used to detect differences.

Results

Statistically significant shape differences were observed for the maxillary incisor in the MSX1 family compared with the controls on the following parameters: surface area, buccolingual dimension, squareness, and crown volume (P?≤?0.002). Molar crown shape was unaffected.

Conclusions

A better understanding of dental phenotype-genotype associations may contribute to earlier diagnosis of some multiple-anomaly congenital syndromes involving dental anomalies.

Clinical relevance

A “shape database” that includes associated gene mutations resulting from developmental syndromes may facilitate the genetic identification of hypodontia cases.
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12.

Objectives

Extranodal lymphomas affecting the head and neck infrequently arise within the jaw bones. Although clinical examination and conventional radiography may initially suffice for such lesions arising within the mandible, those arising within the maxillary alveolus generally require cross-sectional imaging because of the complex anatomy of this region. This study was performed to determine the prevalence, demographic characteristics, and clinical presentations of these lesions and the imaging modalities used for their diagnosis.

Study design

A systematic review (SR) on case series and another SR on case reports were performed to investigate the demographic, clinical, and radiological features of extranodal lymphomas arising within the maxillary alveolus.

Results

Most case series were derived from just four nations, whereas the case reports were derived from a wider range of ethnicities. The more detailed case reports significantly reported at least one imaging modality. Most patients were aware of their lesions for nearly 2 months before presentation. The most frequent symptom was swelling. Most case reports included a provisional diagnosis, the most frequent of which was dental infection followed by squamous cell carcinoma.

Discussion

Extranodal lymphomas arising within the maxillary alveolus were sufficiently frequent in four communities to be reported in two or more case series, and the occasional single case report indicated that such lesions are more widespread globally. Although the SR on case series revealed differences in the relative period prevalence and maxillary/mandibular ratio, the SR on case reports revealed details of the clinical presentation and imaging modalities used.
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13.

Background

Prune belly syndrome is a rare condition produced by an early mesodermal defect that causes abdominal abnormalities. However, the literature indicates that disturbances related to ectodermal development may also be present. This is the first case report in the literature to suggest that dental abnormalities are part of the broad spectrum of clinical features of prune belly syndrome. Because the syndrome causes many serious medical problems, early diagnosis of abnormalities involving the primary and permanent dentitions are encouraged.

Case presentation

The authors report the clinical case of a 4-year-old Caucasian boy with prune belly syndrome. In addition to the triad of abdominal muscle deficiency, abnormalities of the gastrointestinal and urinary tracts, and cryptorchidism, a geminated mandibular right central incisor, agenesis of a mandibular permanent left incisor, and congenitally missing primary teeth (namely, the mandibular right and left lateral incisors) were noted.

Conclusion

This original case report about prune belly syndrome highlights the possibility that dental abnormalities are a part of the broad spectrum of clinical features of the syndrome. Therefore, an accurate intra-oral clinical examination and radiographic evaluation are required for patients with this syndrome in order to provide an early diagnosis of abnormalities involving the primary and permanent dentitions.
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14.

Background

Mixed dentition space analysis methods using regression equations, namely, Moyers’ analysis and Tanaka-Johnston analysis are commonly used around the world. However, the applicability of these analyses among different racial groups have been questioned. The primary objective of this study was to assess the applicability of the Moyers’ and Tanaka-Johnston analyses among Nepalese Mongoloids and to develop regression equations for the same population if needed.

Methods

One hundred (50 males and 50 females) pre-treatment study models of the Nepalese Mongoloid patients undergoing orthodontic treatment were retrieved from the archives of the department of Orthodontics. The mesiodistal widths of mandibular incisors and widths of canines and premolars of all 4 quadrants were measured by a single investigator using a digital caliper to the nearest 0.01?mm. Predicted widths of canines and premolars were obtained using standard Moyers’ and Tanaka-Johnston analyses and then compared with the measured widths.

Results

The measured widths of canines and premolars were significantly different from the predicted widths obtained from Moyers’ and Tanaka-Johnston analyses. Strong and positive correlations were found between the sum of mesiodistal widths of mandibular incisors and the sum of mesiodistal widths of canines and premolars in males (0.73 for maxillary arch and 0.68 for mandibular arch) and females (0.64 for maxillary arch and 0.79 for mandibular arch).

Conclusions

The Moyers’ and Tanaka-Johnston analyses did not accurately predict the mesiodistal width of unerupted canines and premolars for Nepalese Mongoloid population. Hence, new regression equations have been developed for this population. However, validation studies should be conducted to confirm the applicability and accuracy of these equations.
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15.

Objective

We analyzed patients with advanced parotid malignancy requiring proximal facial nerve exposure undergoing mastoidectomy versus lateral temporal bone resection to determine differences in local and distant recurrence.

Study design

The study design is a case series with chart review.

Setting

The setting is in Tertiary care practice in Fort Worth, Texas from January1998 to January 2014.

Subjects and methods

The study included 120 patients with advanced parotid malignancy, 82 males between 19 and 87 years, and 38 females between 26 and 83 years. Patients with no overt bone involvement were treated with parotidectomy and mastoidectomy for exposure of the proximal facial nerve, and patients with clinically suspected (radiographic imaging or clinical fixation) bone involvement were treated with parotidectomy and lateral temporal bone resection. Follow up ranged from a minimum of 18 months to 11 years following surgery.

Results

Sixty patients were treated with mastoidectomy and 60 were treated with lateral temporal bone resection. In patients treated with mastoidectomy, 13 had local recurrence and 7 had distal recurrence. In patients treated with lateral temporal bone resection, 2 had local recurrence while 9 had distant recurrence. Statistical analysis revealed that patients treated with mastoidectomy developed local recurrence (p = 0.0022) more commonly than those treated with lateral temporal bone resection. There was no significant difference in distant recurrence between both groups (p = 0.5949).

Conclusions

Patients with advanced parotid malignancy should be treated aggressively with parotidectomy and lateral temporal bone resection regardless of bone involvement due to increased risk of local recurrence in those treated with mastoidectomy alone.

Level of evidence

Level of evidence is a 4 case series.
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16.

Objectives

The present study investigated the position and relationship of the maxillary third molars to the maxillary sinus. These molars were detected to have a close relationship with the maxillary sinus based on panoramic images, using cone-beam computed tomography (CBCT).

Methods

This retrospective study evaluated 162 impacted third molars from 100 patients that showed a superimposed relationship between the maxillary sinus and third molars on panoramic images obtained from CBCT. CBCT images were used to assess the horizontal (buccopalatal) and vertical positions of the maxillary sinus relative to the maxillary third molars, proximity of the roots to the sinus, and angulation and depth of the third molars. The associations among the angulation, depth of third molars, and horizontal and vertical positions of the maxillary sinus relative to the third molar findings were examined using Chi square tests.

Results

Based on the winter classification, the most frequent tooth position was vertical (59.9 %), followed by mesioangular (14.2 %), distoangular (9.9 %), and others. Most impacted teeth were at the level between the occlusal and cervical levels of the adjacent second molar. Regarding the relationships of the maxillary third molars with the maxillary sinus examined on CBCT, vertical type III (buccal root related with maxillary sinus) (34 %) and horizontal type 2 (maxillary sinus located between roots) (64.8 %) were seen most frequently.

Conclusions

The relationship between the maxillary sinus and third molar roots should be considered during extraction. When a risk of sinus perforation is predicted in an extraction, a presurgical CBCT examination could be valuable.
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17.

Background

The quantification of fluorosis using fluorescence imaging (QLF) hardware and stain analysis software has been demonstrated in selected populations with good correlation between fluorescent image metrics and TF Index scores from photographs. The aim of this study was to evaluate the ability of QLF to quantify fluorosis in a population of subjects (aged 11–13) participating in an epidemiological caries and fluorosis survey in fluoridated and non-fluoridated communities in Northern England.

Methods

Fluorescent images of the maxillary incisors were captured together with standardized photographs were scored blind for fluorosis using the TF Index. Subjects were excluded from the analysis if there were restorations or caries on the maxillary central incisors.

Results

Data were available for 1774 subjects (n=905 Newcastle, n=869 Manchester). The data from the fluorescence method demonstrated a significant correlation with TF Index scores from photographs (Kendall’s tau = 0.332 p<0.0001). However, a number of additional confounding factors such as the presence of extrinsic stain or increased enamel translucency on some subjects without fluorosis or at low levels of fluorosis severity had an adverse impact on tooth fluorescence and hence the outcome variable. This in conjunction with an uneven distribution of subjects across the range of fluorosis presentations may have resulted in the lower than anticipated correlations between the fluorescent imaging metrics and the photographic fluorosis scores. Nevertheless, the fluorescence imaging technique was able to discriminate between a fluoridated and non-fluoridated population (p<0.001).

Conclusions

Despite confounding factors the fluorescence imaging system may provide a useful objective, blinded system for the assessment of enamel fluorosis when used adjunctively with photographic scoring.
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18.

Aim

The aim of this clinical paper is to introduce a technique to plan for functional maxillofacial reconstructions.

Materials and Methods

Preoperative dental casts were made of the patient and mock surgery performed on the casts. A fibula analogue was then placed in an ideal functional reconstruction position. New dentures were fabricated on the fibula analogue and drill holes for the placement of implants were placed through the denture. This denture formed as a guide to position the fibula transplant during surgery.

Results

This technique was useful in producing functional and rehabilitative outcomes in cases of both maxillary and mandibular reconstructive surgeries.

Conclusion

The Jugaad technique—denture based inverse planning—is a cost effective method for planning and executing maxillofacial reconstructions using mock surgery on casts and interim dentures.
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19.

Purpose

Surgically assisted rapid maxillary expansion is performed to correct transverse deficiencies of the maxilla, and it is indicated in specific clinical situations. The literature presents different opinions in several aspects, mainly regarding the effect of disjunction of the pterygoid plates. The aim of this study was to evaluate the pattern of maxillary expansion obtained with two surgical techniques, with and without disjunction of the pterygoid plates.

Methods

Twenty patients treated with surgically assisted rapid maxillary expansion for correction of transversal discrepancies were included in this retrospective study and divided into two groups: (G1) patients operated without disjunction of pterygoid plates and (G2) patients treated with release of the pterygoid plates.

Results

There were seven male and 13 female patients, and the mean age was 29.9 years. Cone beam computed tomography images obtained after final activation of the expansion device were evaluated and complete disjunction of the midpalatal suture (type I) was present in 75 % of the patients whereas incomplete disjunction of the midpalatal suture (type II) was observed in 25 %. Chi-square test showed no statistically significant difference between groups (p = 0.606).

Conclusion

No difference was found in relation to the maxillary disjunction pattern irrespective of the treatment given to pterygoid plates.
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20.

Purpose

The relationship between radiographic findings and the occurrence of oroantral perforation is controversial. Few studies have quantitatively analyzed the risk factors contributing to oroantral perforation, and no study has reported multivariate analysis of the relationship(s) between these various factors. This retrospective study aims to fill this void.

Methods

Various risk factors for oroantral perforation during maxillary third molar extraction were investigated by univariate and multivariate analysis. The proximity of the roots to the maxillary sinus floor (root-sinus [RS] classification) was assessed using panoramic radiography and classified as types 1–5. The relationship between the maxillary second and third molars was classified according to a modified version of the Archer classification. The relative depth of the maxillary third molar in the bone was classified as class A–C, and its angulation relative to the long axis of the second molar was also recorded.

Results

Performance of an incision (OR 5.16), mesioangular tooth angulation (OR 6.05), and type 3 RS classification (i.e., significant superimposition of the roots of all posterior maxillary teeth with the sinus floor; OR 10.18) were all identified as risk factors with significant association to an outcome of oroantral perforation.

Conclusion

To our knowledge, this is the first multivariate analysis of the risk factors for oroantral perforation during surgical extraction of the maxillary third molar. This RS classification may offer a new predictive parameter for estimating the risk of oroantral perforation.
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