Arch Length Research Articles

Finite element analysis-aided seismic behavior examination of modular underground arch bridge

In this study, a 3D finite element analysis (FEA) is performed to examine the seismic behaviors of a three-hinge modular underground arch bridge (MUAB) subjected to a series of synthetic ground motions with a wide peak-ground-acceleration (PGA) spectrum. The FEA model of the MUAB under longitudinal and transverse synthetic ground-motion loading is described by several modeling parameters [e.g., arch-to-arch interaction (AAI), soil–structure interaction (SSI), and stiffness of prestressed rebar], to determine its various seismic response characteristics (i.e., maximum displacement, maximum tensile and compressive stresses, and maximum crack depth). The FEA results show that the MUAB’s seismic responses differ with respect to earthquake-loading direction owing to the different levels of seismic resistance associated with the considered modeling parameters. To elucidate the influence of each modeling parameter on the seismic response, we performed MUAB parametric studies featuring different arch lengths, SSI and AAI friction coefficients, and prestressed-rebar stiffnesses. The key findings indicate that the seismic behaviors of MUABs depend on the PGAs and ground-motion directions; furthermore, they exhibited a sensitivity to the arch length and prestressed-rebar stiffness. In addition, the SSI friction coefficient exerted a minor influence on the seismic responses of MUABs, especially on their maximum compressive and tensile stresses and maximum crack depths; meanwhile, the AAI friction coefficient had a moderate influence upon seismic response.

Skeletal and Dental Effects of Twin-Block Appliances in Patients Treated With or Without Expansion.

To compare the skeletal and dental effects of twin-block appliances with or without expansion. From our archives, patients using twin-block appliances were selected. A total of 20 patients with expansion screws were classified as group 1 (10 male, 10 female; mean age 12.48 ± 1.38 years), and 18 patients without screws as group 2 (8 male, 10 female; mean age 12.81 ± 1.16 years). Cephalometric radiographs at pre-and post-treatment were used to evaluate skeletal and dentoalveolar parametric changes; study models and posteroanterior radiographs were used for transverse evaluation. The initial measurements and the treatment-related mean changes within the study groups were analyzed using the Student's t-test. Changes in maxillary skeletal measurements were not statistically significantly different between groups except for A-VRL (P > .05). Mandibular measurements showed an increase in SNB (º) and Co-Gn distance in both groups. However, these changes were similar for both groups (P > .05). The maxillary measurements showed that incisors were proclined in the expansion group and retroclined in the non-expansion group. No significant difference was found between the groups in terms of changes in the skeletal transversal measurements (P > .05). On the study models, the changes in maxillary intercanine and intermolar widths, and in arch length differed to a statistically significant degree between groups (P < .05). The skeletal effects of 2 different types of twin-block appliances in the transversal direction were similar; it was determined that dental expansion was obtained in the maxilla by adding screws to the twin-block appliances.

Occlusal changes in orthodontically treated subjects 40 years after treatment and comparison with untreated control subjects

The objective of this study was to compare the aging changes of the dental arches in orthodontically treated and untreated subjects after a 4-decade follow-up period. This retrospective study analyzed 2 groups. The treated group comprised 29 patients (11 male, 18 female) presenting with Class I or Class II malocclusions orthodontically treated with extractions of 4 first premolars. Dental models taken at pretreatment (12.84years), posttreatment (14.95years), and long-term posttreatment (51.37years) were evaluated. The untreated (control) group consisted of 22 untreated patients with dental models taken at 13.32, 17.82, and 60.95years of age. The dental models were digitized, and the following variables were evaluated: Little irregularity index, intercanine, interpremolar and intermolar widths, arch length, arch perimeter, overjet, and overbite. Interphase comparison of the treated group was performed with repeated measures analysis of variance and Tukey tests. Intergroup comparisons were performed using t tests (P<0.05). Crowding was corrected with treatment but relapsed significantly in the long term. Intercanine width increased with treatment and decreased in the long term. Interpremolar and intermolar widths, arch perimeter, and length decreased with treatment and continued to decrease long-term posttreatment. Overjet and overbite were corrected with treatment and remained stable in the long term. From posttreatment to long-term posttreatment, a greater crowding increase was observed in the treated group than in the untreated group. The treated group demonstrated a greater decrease in mandibular intercanine and maxillary and mandibular interpremolar widths than the untreated sample. Overbite increased in the treated group and decreased in the untreated group. The multiple regression analysis showed that previous 4-premolar extractions orthodontic treatment is significantly associated with anterior crowding in the long term. In the long-term, the treated patients showed relapse of crowding and a decrease in arch form. Long-term changes of treated patients were different from untreated subjects. Relapse might have contributed to greater changes in incisor crowding and arch widths observed in the treated patients.

Characteristics of the Deep Carious Lesions of Primary and Permanent Molars Using IOPA Radiographs

Aim: To determine the site and pattern of deep carious lesion &amp; its consequences on coronal and radicular structures radiographically in primary molars &amp; first permanent molars using IOPA radiographs.&#x0D; Materials and methods: It consisted of 200 IOPA of Deep carious of Maxillary &amp; mandibular of primary (n=100) and permanent molars(n=100) X-rays are collected. IOPA radiographs of Deep carious lesion involving only dentin with radiolucency reaching the inner 1/3 of dentin, clinically cavitated that is RC5 Of the ICMMS criteria were taken. Blinded Radiographic evaluation was done by two persons to rule out inter examiner variability.&#x0D; Results: In primary molars IOPA there was statistically significant difference in Carious adjacent tooth whereas in permanent molars IOPA there was statistical difference in Diffused pattern and lost tooth structures. When compared primary and permanent molars diffused pattern and lost tooth structure showed statistically significant difference.&#x0D; Conclusion: The deep carious lesions definitely lead to loss of crown structure over a period of time and also capable of spread of caries to adjacent teeth due to food impaction &amp; inadequate oral hygiene. Hence leading to loss of function and arch length.

Implications of Permanent Teeth Dimensions and Arch Lengths on Dental Crowding during the Mixed Dentition Period

Dento-alveolar disharmony with crowding is a common reason for orthodontic treatment with not fully understood or unequivocally demonstrated causes. This study investigated the correlations between teeth dimensions, arch lengths, and crowding during the mixed dentition period. A cross-sectional study on 100 dental casts of patients with class I malocclusions was performed. Dental arches were classified as non-crowded, moderately crowded, severely crowded, and spaced. The mesio-distal widths, bucco-lingual sizes, and crown proportions of permanent teeth were assessed. The results indicated that arch length measurements showed smaller values in crowded arches. The mesio-distal dimensions of upper central incisors and lower lateral incisors were larger in patients with crowding. The bucco-lingual dimensions of upper incisors were decreased, the bucco-lingual dimensions of lower central incisors and permanent first molars were increased in crowded arches. Upper incisors and lower lateral incisors presented larger crown proportions in crowding cases. Low negative correlations were found between mesio-distal diameters of maxillary central incisors, lower lateral incisors, lower permanent first molars, and the values of arch space discrepancies. In conclusion, crowding in the mixed dentition could be associated with reduced arch lengths, increase in mesio-distal sizes of incisors and lower permanent first molars, and variations of bucco-lingual dimensions and crown proportions of incisors and lower permanent first molars.

Developmental changes of the facial skeleton from birth to 18 years within a South African cohort (A computed tomography study)

Skeletal remains are often found on a crime scene in which a forensic anthropologist is then consulted to create a biological profile, which includes the estimation of age, sex, ancestry and stature. The viscerocranium plays an important role in the formation of a biological profile. However, to utilise the viscerocranium for age estimation, population specific normative data and knowledge of the development of the viscerocranium is required. Therefore, this study aimed to investigate the developmental changes from birth to 18 years of age of the facial skeleton of individuals from a South African cohort. This study comprised of 239 computed tomography (CT) scans (128 males; 111 females). The viscerocranium was subdivided into five regions viz.: orbital, nasal, midfacial, maxillary and mandibular. The linear parameters in each region were correlated to age to identify the developmental growth patterns of the viscerocranial regions according to male and female. The measurements which displayed the highest correlations with age were used to develop formulas which could be used for age estimation. The results of this study showed that the measurements in the orbital, midfacial, maxillary and mandibular regions experienced rapid growth between 0 and 5 years of age, with the nasal region increasing steadily over time. It was noted that males displayed overall larger measurements than females except for the anterior interorbital distance and both right and left zygomatic arch lengths (ZAL). Although only the left orbital height, nasal aperture height and mandible width displayed statistically significant size differences according to sex (p ≤ 0.05). The measurements which showed the highest correlations to age were the zygomatic arch distance (r = 0.8842, p < 0.001), ZAL (right: r = 0.8929, p < 0.001; left: r = 0.8656, p < 0.001) and the mandible width (r = 0.8444, p < 0.001). Formulas were derived for the measurements that could be used to forensically estimate age within a subadult cohort.

Aortic Geometric Alteration Associated With Acute Type B Aortic Dissection: Angulation, Tortuosity, and Arch Type.

Background: Acute type B aortic dissection is a highly serious aortic pathology. Aortic geometric parameters may be useful variables related to the occurrence of acute type B aortic dissection (aTBAD). The aim of the study is to delineate the alteration in aortic geometric parameters and analyze the specific geometric factors associated with aTBAD.Methods: The propensity score matching method was applied to control confounding factors. The aortic diameter, length, angulation, tortuosity, and type of aortic arch of the aTBAD and control group were retrospectively analyzed via three-dimensional computed tomography imaging created by the 3mensio software (version 10.0, Maastricht, The Netherlands). The geometric variables of true lumen and false lumen in the descending aorta were measured to estimate the severity of aortic dissection. Multivariable logistic regression models were used to investigate the significant and specific factors associated with aTBAD occurrence. The area under the receiver operating characteristic curve (AUC) was used to estimate the performance of the model.Results: After propensity score matching, 168 matched pairs of patients were selected. The ascending aorta and aortic arch diameters were dilated, and the ascending aorta and total aorta lengths were elongated in aTBAD group significantly (P < 0.001). The ascending aorta and aortic arch angulations in the aTBAD group were sharper than those of the controls (P = 0.01, P < 0.001, respectively). The aortic arch and total aorta tortuosities were significantly higher in the aTBAD group (P = 0.001, P < 0.001, respectively). There were more type III arch patients in the aTBAD group than the controls (67.9 vs. 22.6%). The true lumen angulation was sharper than that in the false lumen (P < 0.01). The true lumen tortuosity was significantly lower than that in the false lumen (P < 0.001). The multivariable models identified that aortic arch angulation, tortuosity, and type III arch were independent and specific geometric factors associated with aTBAD occurrence. The AUC of the multivariable models 1, 2, 3 were 0.945, 0.953, and 0.96, respectively.Conclusions: The sharper angulation and higher tortuosity of aortic arch and type III arch were the geometric factors associated with aTBAD in addition to the ascending aorta elongation and aortic arch dilation. The angulation and tortuosity of the true and false lumens may carry significant clinical implications for the treatment and prognosis of aTBAD.

PERBANDINGAN UKURAN GIGI DAN DIMENSI LENGKUNG ANTARA GIGI TANPA BERJEJAL DENGAN GIGI BERJEJAL

Tooth size and arch dimensions are hereditary factors that play a role in the occurrence of crowding teeth. The purpose of this study was to determine the difference in tooth size and arch dimensions between crowding and crowding teeth. This type of research is an observational study with a cross sectional approach. The sample of this study consisted of two groups. The sample of this study was a dental study model, which consisted of 36 pairs in each group. The results showed the total mesio-distal width of the maxillary anterior teeth (45.95 mm and 48.26 mm), the mandibular anterior teeth (35.92 mm), and 38.16), the maxillary teeth (95.82 mm and 99.47 mm), the mandibular teeth (87.60 mm and 91.50 mm), the inter-canine width maxillary buccal region (37.03 mm and 34.85 mm), maxillary inter-canine width palatal region (26.53 mm and 25.69 mm), buccal area of ​​mandibular inter-canine width (28.38 mm and 27.75 mm), the mandibular inter-canine width in the lingual area (20.38 mm and 19.90 mm), the maxillary inter-molar width in the buccal area (62.73 mm and 60.60 mm), the maxillary inter-molar width in the palatal area (37.86 mm and 35.10 mm), mandibular inter-molar width buccal area (56.51 mm and 55.31 mm), mandibular inter-molar width lingual area (34.10 mm and 31.66 mm), arch length maxillary arch (37.57 mm and 37.76 mm), mandibular arch length (32.63 mm and 32.77 mm), maxillary arch perimeter (96.95 mm and 94.68 mm), and mandibular arch perimeter (87.86 mm and 85.83 mm), Bolton's anterior ratio (78.19% and 79.13%), and Bolton's overall ratio (91.43% and 92.03%). The conclusion of the study showed that the crowding group had larger tooth size, narrower arch width, narrower arch perimeter, longer arch length, and larger anterior ratio and Bolton overall ratio compared to the crowding group.

Frequency, Pattern and Rationale of Tooth Extractions Among Orthodontic Patients: A 10-year Tertiary Institution Experience

Background and objectives: Tooth extractions are a vital aspect of orthodontic management that enables the orthodontist to achieve good aesthetics and function as well as long term treatment stability for the patient. Extractions may be necessary for various reasons among which are tooth size arch length discrepancy (TSALD), increased overjet and facial profile. The aim of this study was to determine the prevalence, pattern and rationale of tooth extraction among orthodontic patients attending the Orthodontic Unit of the Department of Child Dental Health, University of Port Harcourt Teaching Hospital. Methods. A retrospective study of a cohort of patients who attended one of the outpatient Orthodontic Clinics in the Department of Child Dental Health, University of Port Harcourt Teaching Hospital, Port Harcourt, Nigeria between 2011 and 2021. Data was collected from the patients’ records. Results. A total of 175 patients comprising 70(40%) males and 105(60%) females were included in the study. 67(38.3%) patients had at least one extraction. Twenty-eight (41.8%) extraction cases had extraction of the first premolars. Two-unit extractions of the maxillary first premolars (13, 46.4%) was the most frequent extraction pattern. Eight (29.6%) had extraction of primary canines only. Twenty-seven (40.3%) participants had extractions due to increased overjet. Over a third of the patients had extraction of at least one tooth. Conclusion. Two-unit extractions of maxillary first premolar was the commonest extraction pattern. Increased overjet was the commonest reason for extraction.

Does arch length preservation in mixed dentition children affect mandibular second permanent molar eruption? A systematic review and meta-analysis

BackgroundArch length preservation strategies utilize leeway space or E-space in the mixed dentition to resolve mild to moderate mandibular incisor crowding. The purpose of this systematic review of the literature was to analyze the effects of arch length preservation strategies in on mandibular second permanent molar eruption.MethodsA search for relevant articles published from inception until May 2020 was performed using PubMed/Medline, Cochrane databases, Clinicaltrials.gov, Google scholar and journal databases. Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were adopted for the conduct of the systematic review. Using RevMan 5.3 software, the most pertinent data were extracted and pooled for quantitative analysis with 95% confidence intervals. Heterogeneity was analyzed by using Cochran Q test and I squared statistics.ResultsA total of 5 studies involving 855 mixed dentition patients with arch length preservation therapy were included in the qualitative analysis. Pooled estimate of the data from two studies revealed 3.14 times higher odds of developing mandibular second molar eruption difficulty due to arch length preservation strategies using lingual holding arch (95% CI; OR 1.10–8.92). There was no heterogeneity found in the analysis. The certainty levels were graded as very low.ConclusionsThis systematic review demonstrates that arch length preservation strategies pose a risk for development of mandibular second molar eruption disturbances, but the evidence was of very low quality.Registration number: CRD42019116643.

Foot-surface-structure analysis using a smartphone-based 3D foot scanner

A thorough understanding of the influence of the foot skeletal structure on hallux valgus (HV) is required for HV prevention. We developed a system using a 3D foot scanner on a smartphone to clarify the relationships between foot features and HV risk. Two-dimensional video images were recorded on a smartphone, sent to a computer or cloud server, and used to construct a 3D foot-feature model, considering 10 foot features associated with HV. The participants (419 individuals, aged 40-89 years) stood with their toes 12cm apart and heels 8cm apart during video recording. The height and weight were measured for body-mass index calculation. Age-dependent foot-feature variations were observed slightly for males and distinctively for females. For females, the great toe-first metatarsal head-heel (GFH) angle associated with HV increased with age, i.e., the GFH angle increased with age, suggesting that HV increased with age. Multiple regression analysis revealed that the features determining the GFH angle are the second toe-heel-navicular angle, bone distance axis, and transverse arch length and height. The adjusted coefficients of determination were 0.54 and 0.52 for males and females, respectively. This approach enables simple foot structure assessment for HV risk evaluation.

Influence of Bone-Borne Trans-Sutural Distraction Osteogenesis Therapy on the Hard Palate of Growing Children With Cleft Lip and Palate.

The efficacy of trans-sutural distraction osteogenesis therapy (TSDO) in treating midfacial hypoplasia in children with cleft lip and palate has been confirmed. However, few studies have reported that changes occur in the palate after TSDO treatment. To study the effect of TSDO on palatal morphology and its relative position in the craniofacial region, we retrospectively collected and measured the computed tomography images of 29 growing children with cleft lip and palate and midfacial hypoplasia, before and after TSDO. The results showed that the length and height of the palate did not change significantly, but the width and arch length increased, and the anterior area was more pronounced than the posterior area, with the median palatine suture still centered without obvious deviation. This suggests lateral palate growth after distraction, most likely around the median palatine suture. The distance from the palate to the cranial base also increased after distraction, and the anterior nasal spine moved forward, whereas the palate rotated by an average of 10.04° downward from the center of the anterior nasal spine. The increasing distance between the palate and cranial base may result from the growth of the nasal bone or the skull base. The oropharyngeal airway volume was also increased by an average of 2256.36 mm3, which may be beneficial to children's ventilatory function. In conclusion, TSDO therapy has influence on patients' palatal morphology and position, which should be considered before surgery.

Changes in the Transverse Dimension of the Maxillary Arch of 5-Year-Olds Born With UCLP Since the Introduction of Nationwide Guidance.

Objective:To determine whether the transverse dimensions of the maxillary arch of 5-year-old children with unilateral cleft lip and palate (UCLP) have changed following centralization of cleft services in the United Kingdom.Design:Retrospective cross-sectional study.Setting:Digital analysis of UCLP maxillary dental casts.Participants:All available maxillary dental casts from 5-year-old participants of the Clinical Standards Advisory Group (CSAG, N = 114) and Cleft Care UK (CCUK, N = 175) studies.Interventions:Quantitative measurements of the intercanine width (ICW), intermolar width (IMW), and the distance from the midline to the greater and lesser side canine (GC/LC) and greater side and lesser side second primary molar (GE/LE). Degree measurements of the greater and lesser arch form angles, arch length, anterior palatal depth (APD), and posterior palatal depth were also measured.Main outcome:Differences between the transverse dimensions of the maxillary arch for the CSAG and CCUK cohorts.Results:In 5 (ICW, IMW, LC, LE, and APD) of the 11 measurements, there was a statistically significant difference between the CSAG and CCUK cohorts. In all of these, the CCUK values were greater than CSAG.Conclusions:There have been small but positive improvements for the transverse maxillary dimensions since centralization of the UK cleft service.

Treatment of deep overbite in mixed dentition: a clinical case report

Relevance. Deep overbite is one of the most frequent malocclusions in children and teenagers of different ages. Distal occlusion with a deep overbite is the most common (59.6-67.6% according to the literature) in early mixed dentition. Most Russian and international authors state in their research that the severity of malocclusion increases with age. The treatment of the pathology in children is relevant due to deterioration of the deep overbite with age, worsening of functional disorders.Materials and methods. The study analyses the treatment results of a child with a deep bite using the authors’ technique.Results. The study demonstrated the advantages of the authors’ technique. The treatment allowed achieving normal dentoalveolar heights in the posterior mandible on molar and premolar eruption, establishing the correct relationship between the upper and lower dental arches that promoted harmonious development of the child’s maxillofacial area. The treatment regulated the length and width of the upper dental arch and corrected its form. The active intrusion of the lower incisors and extrusion of the lower posterior teeth were observed during the treatment. The curve of Spee was restored, and an increased overlap reduced. Occlusal contacts of posterior teeth improved, and deep overbite decreased. The technique is easy to use and allows curing 9-12-year-old children in a short period (7-10 months).Conclusions. The suggested technique treats deep overbite as well as creates conditions for the further harmonious development of the maxillofacial area. Thus, it can be recommended for the treatment in early mixed dentition.

Comparison of Dental Arch Width and Length Parameters in Patients With Obstructive Sleep Apnea and a Control Group: A Pilot Study

Comparison of Dental Arch Width and Length Parameters in Patients With Obstructive Sleep Apnea and a Control Group: A Pilot Study

Analysis on Finite Element Grid Size and Discrete Error for Super-high Arch Dams

Compared with the world super-high arch dams with height more than 200 meters, the six super-high arch dams already built or under construction in China share the same special body shapes with higher ratios for both top/bottom width and thickness, and for top arch length with dam height. Also all of them are subjected to big top-level water pressures. In the paper, the computational formulation of thermal-coupled structure of hollow sphere similar to arch dam in shape and load-subjected is derived first and analysis of errors from the finite element method compared with the analytic solution is made. Then, a typical super-high arch dam is taken as the example of structure analysis including dam body mesh division, stress distribution, error estimation. Employing quadrilateral Coupled-field tetrahedral element with size decided by the bottom thickness multiple of arch crown beam, performance of mesh division and analysis for complex model is done conveniently and fast. Also, the paper investigates the error and convergence of results with different mesh density, discusses the special stress states of arch dam, and proposals acceptable dam body element size from calculation accuracy, convenient operation and elapsed time when performance is carried on with strong coupling on conmen personal computers. The research work indicates that errors of analysis results in most part of area are very small excepting those for the local singularity and concentration part when the dam body element size is decreased to 0.25 multiple of bottom thickness of arch crown beam, with dam body energy error norm less than 10% and consuming a couple of elapsed time. The conclusion should be common for the arch dams in China as they have similar shape.

Early Maxillary Expansion with the Ni-Ti Memory Leaf Expander-A Compliance-Free Fixed Slow Maxillary Expansion Screw: A Report of 2 Cases.

Transversal problems such as crowding and crossbite are one of the most common problems dealt with in early orthodontic treatments. Early correction of these problems may ease or even eliminate the future need for treatment. This paper presents the management of 2 cases with transverse discrepancy using the Ni-Ti Memory Leaf Expander--a new compliance-free slow maxillary expansion appliance. The total treatment time for both cases was 9 months. In both cases, the inter-canine, inter-premolar, and inter-molar distances, as well as the arch length, have all increased.

Compare Two Methods of Dental Arch Length Measurements on Digital Dental Models

Purpose: Accurate space discrepancy evaluation is important in treatment planning. Straight-line segments and brass wire method are the most common methods in arch length assessment. However, using segments causes underestimation, while more reliable brass wire method shows lower reproducibility. The aim of our study is (1) to compare the difference between conventional segmental distance method (SD) and a new method, ideal arch form (IA), and (2) to assess the reproducibility and reliability of two methods by means of digital models. Materials and methods: Thirty sets of digital dental models presented full permanent dentition and Angle’s Class III malocclusion were included. The dental arch length was assessed with two methods: SD method and IA method. Paired-t test was used to compare two methods; Pearson’s correlation coefficient was used to analyze the correlated variables with inter-group difference; and interclass correlation coefficient was used to evaluate the reproducibility. Result: Arch length in IA group was 1.86 and 0.86 mm larger than SD group in upper and lower arch, respectively (pr= -0.39, pr= 0.40, pConclusion:The SD method showed high consistency but low reliability in short upper arches and crowding lower arches. On the other hand, the IA method can represent the real arch length regarding to the basal bone, and simply be constructed and measured with digital software with high reproducibility.

Malocclusion and oral health-related quality of life among young Danish adults. Is there a difference between subjects who received orthodontic treatment during adolescence and subjects without treatment need? A cross-sectional study

Objectives To evaluate and compare malocclusion traits and oral health-related quality of life (OHRQoL) between untreated young adults assessed to have no orthodontic treatment need during childhood, and young adults treated orthodontically during childhood. In addition, to investigate the relationship between malocclusion and OHRQoL. Materials and methods One hundred undergraduate students were screened for eligibility. Subjects had intraoral scans and completed OHIP-14 questionnaires. Angle molar relationship, overjet, overbite, arch length and width, Little's Irregularity Index (LII), Peer Assessment Rating (PAR) index and Dental Aesthetic Index (DAI) scores were assessed. Unpaired t-tests were used to compare outcomes between treated and untreated subjects. Multiple regression analyses were conducted to model the relationship between OHIP-14 and several prognostics simultaneously. Results Ninety-six subjects were included (mean age ± SD = 23.7 ± 1.8 years): 41 treated and 55 untreated. The untreated subjects had significantly higher LII (p = .02), PAR (p = .01), DAI (p < .01) and overbite (p = .03). The treated subjects had significantly larger inter-canine and inter-premolar distances. No relationship was found between OHIP-14 and LII, PAR, DAI, age, gender and presence/absence of previous orthodontic treatment. However, the DAI score was significantly correlated with the OHIP-14 functional limitation domain. Conclusions Untreated subjects had significantly higher LII, PAR and DAI scores than the treated subjects. DAI score was significantly correlated with the OHIP-14 functional limitation domain.

What’s new for the clinician? Excerpts from and summaries of recently published papers

Pulpectomy is a conservative treatment approach for preventing the premature loss of primary teeth that can result in loss of arch length, insufficient space for erupting permanent teeth, impaction of premolars, and mesial tipping of molar teeth adjacent to the lost primary molar. Pulpectomy is a procedure which involves removal of the roof of pulp chamber in order to gain access to the root canals which are debrided, shaped, disinfected, and obturated later with a resorbable material. As a result, the tooth can be maintained in the arch without vital pulp tissue, without compromising the function of the tooth. The most common complications associated with pulpectomy, post-operative pain (PP) and/or swelling, commence after treatment. These are always unpleasant experiences for both patients and clinicians. The apical extrusion of infected debris or irrigation solution during the canal preparation or irrigation procedure may worsen the inflammatory response and cause periradicular inflammation and postoperative pain. It is well-documented that the type of irrigation method affects the amount of apically extruded debris (AED) in permanent teeth. No study has evaluated the effect of different needle types on the intensity and duration of PP after pulpectomy in primary molars. Topçuoglu and colleagues reported on a trial that sought to compare the intensity and duration of postoperative pain after pulpectomy using open-ended needles (OEN) versus sidevented needles (SVNs) in primary upper molars.