Direct printed removable appliances: A new approach for the Twin-block appliance.

Removable appliances are an important part of orthodontic treatment. The Twin-block is widely used for Class II correction. Traditionally, an impression, bite registration, and mounted plaster casts are required to fabricate the acrylic appliance, which usually requires a specialized laboratory. This makes the process expensive and also time-consuming. This paper aims to present an innovative approach for the virtual design and direct printing of removable orthodontic appliances, particularly the Twin-block, that can be done in-office without the need for casts or a specialized laboratory.

CAD-CAM-fabricated mini-implant insertion guides for the delivery of a distalization appliance in a single appointment.

This article reports on the technical aspects of using a computer-aided design-computer-aided manufacturing (CAD-CAM) insertion guide for the placement of orthodontic mini-implants used for the purpose of providing anchorage support for maxillary molar distalization. A 10-year-old girl presented with a bilateral full-step Angle Class II molar relationship in the permanent dentition, with anterior arch-length insufficiency and blocked out maxillary canine teeth. The primary treatment objective was to provide an esthetic and functional occlusal outcome, and secondarily to avoid the removal of multiple premolar teeth. The patient was initially treated with an implant-supported distalization device, and the occlusion was subsequently detailed with preadjusted fixed orthodontic appliances. The CAD-CAM procedure facilitates the safe and precise insertion of mini-implants in the anterior palate, potentially broadening the scope of use of palatal mini-implants for less experienced clinicians. The illustrated protocol allows for the insertion of mini-implants and fitting of a prefabricated appliance in a single office appointment.

Maxillary molar mesialization with the use of palatal mini-implants for direct anchorage in an adolescent patient.

A unique clinical challenge presents when dealing with a compromised first permanent molar. A compelling treatment option for consideration is the removal of a nonrestorable first permanent molar, with the subsequent "replacement" through controlled mesial tooth movement of viable second and third molars. To reinforce the anchorage support associated with such a planned movement, indirect or direct implant-supported mechanics may be used. With the use of direct anchorage, orthodontic brackets are not required and space closure can be commenced immediately. In this article, we report the clinical procedure and design of direct-anchorage mechanics used for the successful closure of a maxillary first permanent molar space with the use of an implant-supported appliance (Mesialslider). Treatment was completed in just under 12 months, with successful mesial movement of the maxillary second and third molars without the need for the bonding of orthodontic brackets on the anterior dentition. The result was determined to be stable over a 3-year period.

Antibiotic Prescribing Patterns Among Dental Professionals In Massachusetts.

Purpose: The purposes of this study were to investigate prescribing patterns of antibiotics for the management of common pediatric oral infections, and to and identify the independent predictors of antibiotic preference across different groups of dental practitioners in Massachusetts, USA. Methods: A cross-sectional survey assessed antibiotic prescribing practices of general dentists, pediatric dentists, endodontists, and oral surgeons based on a series of clinical scenarios where antibiotic coverage may be warranted. Results: The appropriate therapeutic management of patients with facial cellulitis occurred across all clinical groups. Endodontists were least likely to prescribe antibiotics for patients with irreversible pulpitis, and those with pulpal necrosis with associated parulis. Seventy-four percent of respondents prescribed antibiotics for patients suffering from pericoronitis and trismus. Conclusion: With the exception of the management of facial cellulitis, adherence to published guidelines for the prescription of antibiotics is low. Specifically, antibiotics are being prescribed too often for patients with tooth pain or localized abscesses and infrequently when the systemic spread of infection is less obvious, such as with trismus but no fever. Universally promulgated guidelines formulated by professional bodies may lead to improved adherence and a reduction in negative outcomes resulting from the overprescription of antibiotics.

CAD-CAM design and 3-dimensional printing of mini-implant retained orthodontic appliances.

The objective of this article was to illustrate the digital process in the custom fabrication of metallic mini-implant supported appliances. An implant-supported appliance was produced for a patient using a CAD-CAM procedure without a physical impression or a printed model. The work flow consisted of mini-implant insertion into the palate, recording an intraoral digital scan, digital design with incorporation of a scanned expansion mechanism, direct 3-dimensional metal printing via laser melting, laser welding of the hyrax mechanism, insertion, and activation of the appliance. The favorable clinical outcome demonstrated that this procedure is an efficient and viable method for constructing an implant-supported palatal metallic appliance.

Skeletally anchored mesialization of molars using digitized casts and two surface-matching approaches : Analysis of treatment effects.

PURPOSE: To (1) quantify the three-dimensional treatment effect of a Mesialslider appliance using superimposed digital models, (2) to evaluate anchorage loss (measured by incisor displacement), and (3) to assess agreement between two different matching approaches, i.e., control point (CP)-based and iterative closest point (ICP) matching. METHODS: In a retrospective study, the effects of a skeletally anchored uni- and bilateral mesialization appliance (Mesialslider) as well as simultaneous mesialization and distalization appliance (Mesio-Distalslider) were evaluated in 48 subjects (aged 11-53 years). Pre- and posttreatment casts were digitized and superimposed with two different approaches, i.e., using ten manually selected control points located at the anterior palate and by means of an automated ICP-matching approach using a standardized palatal reference area. The treatment effects were evaluated using control points on the maxillary central incisors and maxillary molar teeth, and the methods were compared through the application of linear regression analyses and computation of alignment errors. RESULTS: Average upper molar mesialization was 6.3 ± 2.6 mm. Anchorage loss, designated as the mean amount of upper incisor displacement, was less than 0.5 mm in all dimensions investigated. Using the measurement method sufficient registration was possible using both approaches and corresponding tooth movements were significantly correlated (p < 0.01). CONCLUSIONS: Accurate measurements of tooth displacement can be performed using both CP- and ICP-based matching approaches. Within the limits of performing a retrospective study, a premolar width of molar mesialization appeared possible without clinically relevant anchorage loss.

Orthodontic Treatment: Real Risk for Dental Age Estimation in Adults?

Dental age estimation becomes a challenge once the root formation is concluded. In living adults, one dental age indicator is the formation of secondary dentine, also associated with orthodontic treatment as well as root shortening. The aim of this study was to establish whether these secondary effects of orthodontic treatment could generate a statistically significant difference in dental age estimations when using Kvaal's method. The study sample included 34 pairs of pre- and postorthodontic panoramic radiographs, from different individuals with exactly the same age and sex distribution. Females 65%, median age 17.5 years, and males 35%, median age 22.5 years, were included. After data collection, dental age was estimated per tooth using formulae previously published. The risk of obtaining over-estimation of age was calculated. (RR = 1.007). The changes caused by orthodontic treatment do not have any significant effect on age estimation when Kvaal et al.'s method is applied on panoramic radiographs.

Three-Dimensional Analysis of Nasal Symmetry Following Primary Correction of Unilateral Cleft Lip Nasal Deformity.

OBJECTIVE: To evaluate nasal symmetry using three-dimensional photogrammetry following primary tip rhinoplasty with or without an internal splint in patients with unilateral complete cleft lip/palate. DESIGN: We captured three-dimensional images of patients with unilateral complete cleft lip/palate who underwent nasolabial repair by rotation-advancement of the lip and primary tip rhinoplasty, either with or without an internal resorbable splint, and normal control subjects. We assessed nasal symmetry by identifying the plane of maximum symmetry and the root-mean-square deviation between native and reflected surfaces. PATIENTS/PARTICIPANTS: We imaged 38 controls and 38 subjects with repaired unilateral complete cleft lip/palate (20 with, 18 without an internal splint). RESULTS: Nasal asymmetry root-mean-square deviation clustered between 0.19 and 0.50 mm (median = 0.24 ± 0.08 mm) for controls; whereas, those with repaired unilateral complete cleft lip/palate ranged from 0.4 to 1.5 mm (median = 0.75 ± 0.40 mm). Although root-mean-square deviation ranges overlapped, patients with repaired unilateral complete cleft lip/palate had significantly greater asymmetry than controls (P < .001). We found no difference in asymmetry between patients with or without an internal splint (P = .5). CONCLUSIONS: Three-dimensional photogrammetry was used to successfully compare symmetry among different patient and control groups. Although "normal" nasal symmetry was attained in some patients following cleft lip/nasal repair, most had persistent asymmetry compared with normal controls. Placement of a resorbable internal splint did not improve symmetry in patients with unilateral complete cleft lip/palate.

Application of the Kvaal method for adult dental age estimation using Cone Beam Computed Tomography (CBCT).

Different non-invasive methods have been proposed for dental age estimation in adults, with the Kvaal et al. method as one of the more frequently tested in different populations. The purpose of this study was to apply the Kvaal et al. method for dental age estimation on modern volumetric data from 3D digital systems. To this end, 101 CBCT images from a Malaysian population were used. Fifty-five per cent were female (n = 55), and forty-five percent were male (n = 46), with a median age of 31 years for both sexes. As tomographs allow the observer to obtain a sagittal and coronal view of the teeth, the Kvaal pulp/root width measurements and ratios were calculated in the bucco-lingual and mesio-distal aspects of the tooth. From these data different linear regression models and formulae were built. The most accurate models for estimating age were obtained from a diverse combination of measurements (SEE ±10.58 years), and for the mesio-distal measurements of the central incisor at level A (SEE ±12.84 years). This accuracy, however is outside an acceptable range in for forensic application (SEE ±10.00 years), and is also more time consuming than the original approach based on dental radiographs.

Wear-time recording during early Class III facemask treatment using TheraMon chip technology.

Successful intervention in a developing Class III malocclusion with facemask protraction therapy depends on a patient's ability to adhere to the recommendations for duration of appliance wear. In this article, we report the introduction of a novel approach for tracking of the duration of application of a protraction facemask, with the incorporation of a "FaceMon" sensor (TheraMon, microelectronic system; MC Technology GmbH, Hargelsberg, Austria) to track wear time. A 9-year-old boy with a Class III malocclusion was successfully treated with a modified alternate rapid maxillary expansion and constriction protocol and intermittent application of a hybrid hyrax-protraction facemask combination. The average duration of wear of the facemask was measured at 10.8 hours per day. The use of an objective measuring device may have implications for the development of treatment strategies, since patient responses may be able to calibrated in relation to compliance.

Closure of an open bite using the 'Mousetrap' appliance: a 3-year follow-up.

Recently, skeletal anchorage devices have been used as anchorage units for upper molar intrusion as a way of correcting an anterior open bite malocclusion. To avoid the surgical procedures associated with the placement of miniplates in the zygomatic area, mini-implants may be inserted palatally or buccally in the alveolar process. However, consideration must be given to the potential risks of root damage and a higher failure rate associated with the placement of temporary anchorage devices (TADs) in the interradicular area. The anterior hard palate provides a safer and more stable alternative for TAD placement. The current paper describes the biomechanical principles and the clinical procedures of 'Mousetrap' mechanics using mini-implants in the anterior palate for upper molar intrusion. The stomatognathic response of maxillary molar intrusion is an autorotation of the mandible and so the sagittal implications for each patient must be considered. The presented patient demonstrates successful correction and stability of the treatment result at a three-year review.

Nasolabial soft tissue changes after Le Fort I advancement.

PURPOSE: To identify the nasolabial soft tissue changes that occur after Le Fort I advancement. MATERIALS AND METHODS: A prospective study of patients who had Le Fort I advancement at the Children's Hospital Boston from 2005 to 2007. The pre- and postoperative anthropometeric nasolabial measurements were recorded by a single examiner. RESULTS: A total of 37 patients with a mean age of 18.6 years at the time of operation and a mean follow-up of 12.6 months were recruited. Nearly one half of the study sample (16 of 37) had cleft lip/palate. Direct anthropometry showed a reduction of the nasal length by 1.3 mm while the nasal tip protrusion increased by 1.1 mm. The nasofrontal angle decreased by 9.8° and the upper lip moved forward by 4.15 mm, reflecting the advancement in the maxilla. The height of the cutaneous upper lip increased by 0.4 mm. No significant differences were found in the soft tissue response observed between the cleft and noncleft subjects. CONCLUSIONS: Le Fort I advancement produces elevation of the nasal tip, as seen by a reduction in the nasal length, an increase in the nasal tip protrusion, and a concomitant reduction in the nasofrontal angle. Additionally, the cutaneous lip height increased, most likely due to an unfurling of the upper lip.