Low-Dose Cone-Beam Computed Tomography for Assessment of Alveolar Clefts: A Randomized Controlled Trial in Image Quality.

BACKGROUND: Children born with an alveolar cleft receive bone grafts for improved function and aesthetics. The cleft area is examined radiologically before and after bone graft. Optimizing radiographic examination protocols is essential to protect these patients from possible delayed radiation injury later in life. This study investigates whether image quality of cone-beam computed tomography (CBCT) exposed with an ultra-low-dose (ULD) protocol is comparable to the clinical default protocol, the standard dose (SD) protocol, in visualizing details of importance in bone grafting of alveolar clefts. METHODS: In this randomized controlled study, 72 patients with unilateral or bilateral alveolar clefts between 9 and 19 years (mean age, 9.5 years) were randomized 1:1 with either a ULD or an SD CBCT examination protocol. The CBCT scans were conducted with a Planmeca ProMax Mid scanner with an 8 × 5-cm field of view. Two experienced radiologists blindly evaluated the images and visibility of cortical bone border, trabecular bone, tooth anatomy, root development, periodontal space, and cleft width. The visibility was categorized as unacceptable, acceptable, or excellent. RESULTS: Mann-Whitney U test showed no significant differences in structure visibility between ULD and SD protocols regarding anatomical structures of interest: cortical bone border ( P = 0.07), trabecular bone ( P = 0.64), tooth anatomy ( P = 0.09), root development ( P = 0.57), periodontal space ( P = 0.38), and cleft width ( P = 0.44). CONCLUSIONS: ULD and standard CBCT protocols provide comparable image quality in terms of structure visibility in the examination of alveolar clefts. The ULD protocol is preferred to the SD protocol because of the lower radiation dose without compromising diagnostic information of CBCT images. CLINICAL QUESTION/LEVEL OF EVIDENCE: Diagnostic, I.

Moving toward patient specificity for devising cone-beam computed tomography field-of-views: A normative maxillary skeletal dimensional analysis.

BACKGROUND: A lack of evidence exists comprehensively assessing skeletal dimensions in a Caucasian population group at different ages. AIM: To provide age- and gender-specific normative skeletal dimensional measurements of the maxillary region using cone-beam computed tomography (CBCT) imaging. DESIGN: Cone-beam computed tomography images of Caucasian patients were acquired and divided into different age groups ranging from 8 to 20 years. Linear measurements were taken to evaluate seven distance-based variables, which included anterior nasal spine-posterior nasal spine (ANS-PNS) distance, bilateral maxillary first molar's central fossae (CF) distance, palatal vault depth (PVD), bilateral palatal cementoenamel junction (PCEJ) distance, bilateral vestibular CEJ (VCEJ) distance, bilateral jugulare distance (Jug) and arch length (AL). RESULTS: A total of 529 patients (243 male, 286 female) were selected. ANS-PNS and PVD showed the highest change in dimensions from 8 to 20 years of age. On the contrary, AL had the least variability in all age groups. Male patients had larger dimensions and showed a significant change in all dimensional measurements (p < .001) than female patients. CONCLUSION: The maxillary linear dimensions varied across different age groups. The presented maxillary normative data could serve as a reference guide for devising patient-specific CBCT field of views.

Dental health of patients with X-linked hypophosphatemia: A controlled study.

Objective: The present study compared the dental health of patients with X-linked hypophosphatemia (XLH) with healthy age- and gender-matched controls to increase our knowledge of the impact of XLH on oral health. Materials and methods: Twenty-two adult patients with XLH in the Stockholm region of Sweden were referred to the Department of Orofacial Medicine at Karolinska Institutet for an extended clinical and radiological examination. Pre-existing radiologic examinations of 44 healthy age- and gender-matched controls were retrieved from the Department of Oral Radiology, at Karolinska Institutet. Results: The 22 patients with XLH (15 females, median age 38 years, range 20-71; 7 males, median age 49 years, range 24-67) had a significantly higher number of root-filled teeth compared to healthy controls (p = .001). In the XLH group, females had significantly better oral health than males, especially concerning endodontic and cariological status (p's = .01 and .02, respectively). Periodontal status differed non-significantly between the XLH and control groups. Conclusion: Patients with XLH had a significantly lower oral health status compared to a healthy population especially concerning endodontic conditions. Male patients with XLH had a higher risk of poor oral health compared to female patients with XLH.

Three-dimensional quantification of the relationship between the upper first molar and maxillary sinus.

OBJECTIVES: The present study aims to describe the relationship between upper first molar roots and maxillary sinus, for the first time with a truly three-dimensional approach. METHODS: From a retrospective cone-beam computed tomography (CBCT) sample of the upper jaw, a total of 105 upper first molars in contact with maxillary sinus from 74 patients (male 24, female 50, mean age 42) were included in the present study. Segmentation of the upper first molar and maxillary sinus in CBCT was performed utilizing a semiautomatic livewire segmentation tool in MeVisLab v.3.1. The segmentations were analyzed in 3-matic Medical 20.0 for root volume and the contact area between upper first molar roots and maxillary sinus. Analysis of variance test was applied to detect statistically significant differences between the roots. RESULTS: The palatal root had the largest contact area with maxillary sinus 27.8 ± 21.4 mm2 (20% of the root area) followed by the mesiobuccal 20.5 ± 17.9 mm2 (17% of the root area) and distobuccal root 13.7 ± 12 mm2 (14% of the root area). A significant difference in the contact area of the different roots of the upper first molar was seen. CONCLUSIONS: This study showed that 70% of the upper first molars were in contact with the maxillary sinus. The palatal root had on average a fifth of its root surface in contact with the sinus, while for mesiobuccal this was a sixth of its root surface and distobuccal roots this was somewhat less. The true 3D relationship could help to better understand maxillary anatomy in relation to occurring pathologies and treatment planning in this area.

CBCT-based assessment of the anatomic relationship between maxillary sinus and upper teeth.

OBJECTIVES: To describe the relationship between maxillary sinus (MS) and upper teeth based on cone beam computed tomographic scans (CBCT). MATERIALS AND METHODS: Based on CBCT maxillary imaging data of 147 patients, distance between MS and apices of canines and posterior maxillary teeth were assessed. Distances between tooth roots and sinus were classified into three groups: distant (>2 mm), close (<2 mm) or in contact with MS. Teeth with apical lesions and uncommon root configurations were excluded. RESULTS: In total, 1075 teeth of maxillary canines, upper premolars and upper molars were included in this study. Teeth most often in contact with MS were the second (89%) and first (81%) maxillary molar without any significant difference (p = 0.19). Roots most often in contact with MS were the mesiobuccal and distobuccal root of the second molar (85% and 76%; p = <0.01) followed by the palatal root of the first molar (73%). A fifth of the upper canines are situated less than 2 mm from MS. CONCLUSIONS: More than four out of five upper molars (first and second) are in a close relationship to the MS. Knowledge of the anatomical relationship between posterior maxillary teeth and the MS is important for diagnosis and treatment in this area.

Is congenital malformation a risk factor for caries development in Swedish adolescents?

OBJECTIVE: The aim of this study was to investigate whether various forms of congenital malformations are risk factors for approximal caries development in Swedish adolescents. MATERIALS AND METHODS: This longitudinal register-based cohort study included all adolescents (n = 18 142) of 13 years of age who resided in the county of Stockholm, Sweden, in 2000. The cohort was followed until individuals were 19 years of age. Dental caries (decayed, missing and filled teeth/surfaces (DMFT/S)) were collected from the Public Health Care Administration in Stockholm. Data concerning pre- and perinatal factors and parental socio-demographic determinants were collected from Swedish National Registers. RESULTS: In a logistic regression analysis, neither congenital malformation nor any sub-group of congenital malformation registered at birth were significantly associated with an enhanced risk of approximal caries increment in adolescents between 13-19 years of age. The final multivariate logistic regression model, adjusted for possible maternal and family socio-demographic confounders, showed that congenital malformation of the 'circulatory system' was significantly associated with a decreased risk of approximal caries increment, between 13-19 years of age (OR = 0.33; 95% CI = 0.12-0.88). CONCLUSIONS: Congenital malformation should not be considered as a risk factor for approximal caries development in Swedish adolescents today. Noticeably, adolescents with congenital heart diseases exhibited less risk of developing approximal caries, which was probably related to prevention programs allocated to these children in Sweden.