Autotransplantation of a surgically removed canine using a customised 3D-printed surgical template.

Autotransplantation is a treatment option with high reported survival rates to replace failing teeth in the anterior maxilla. This treatment requires a multidisciplinary approach from orthodontists, paediatric dentists, restorative dentists, and oral and maxillofacial surgeons to achieve successful outcomes. Success is dependent on many factors including stage of root development, handling of the periodontal ligament, extra-alveolar time and splinting. This case report presents the novel use of digitally designed and three-dimensional (3D) printed surgical templates to aid intraoperatively and reduce the extra-alveolar time. A preoperative cone-beam computed tomography scan allowed digital planning and construction of surgical templates that replicated the exact root dimensions of impacted maxillary canines. These templates were subsequently 3D printed in resin, sterilised and utilised intraoperatively to aid socket preparation before the surgical autotransplantation.

Potential reformatting errors in cone-beam computed tomography for dentoalveolar surgery: a cautionary tale.

We describe the removal of a lower second molar tooth in which preoperative cone-beam computed tomography (CBCT) showed that the inferior alveolar nerve (IAN) was encased in the distal apex of the root of the tooth. During operation the nerve was found to be entirely separate from the apex of the root and not involved. With the wider use of CBCT in the treatment planning of dentoalveolar surgery, this case represents a cautionary tale to the clinician on reliance on clinical imaging and software in guiding the decision making process.

Facial shape and asymmetry in 5-year-old children with repaired unilateral cleft lip and/or palate: an exploratory study using laser scanning.

To investigate the feasibility of facial laser scanning in pre-school children and to demonstrate landmark-independent three-dimensional (3D) analyses for assessment of facial deformity in 5-year-old children with repaired non-syndromic unilateral cleft lip and/or cleft palate (UCL/P). Faces of twelve 5-year-old children with UCL/P (recruited from university hospitals in Cardiff and Swansea, UK) and 35 age-matched healthy children (recruited from a primary school in Cardiff) were laser scanned. Cleft deformity was assessed by comparing individual faces against the age and gender-matched average face of healthy children. Facial asymmetry was quantified by comparing original faces with their mirror images. All facial scans had good quality. In a group of six children with isolated cleft palate coincidence with the average norm ranged from 18.8 to 26.4 per cent. There was no statistically significant difference in facial asymmetry when compared with healthy children (P > 0.05). In a group of six children with UCL with or without cleft palate coincidence with the average norm ranged from 14.8 to 29.8 per cent. Forehead, midface and mandibular deficiencies were a consistent finding, ranging from 4 to 10mm. The amount of 3D facial asymmetry was higher in this group (P < 0.05). Facial laser scanning can be a suitable method for 3D assessment of facial morphology in pre-school children, provided children are well prepared. Landmark-independent methods of 3D analyses can contribute to understanding and quantification of facial soft tissue cleft deformity and be useful in clinical practice.

Removable rapid maxillary expansion.

A novel removable rapid maxillary expansion appliance is described for use in routine clinical practice. The laboratory construction and clinical technique is described, and the advantages of the appliance over conventional rapid expansion devices are highlighted.

The use of implants for anchorage in the correction of unilateral crossbites.

The provision of orthodontic anchorage in the adult patient can be compromised due to reduced periodontal support, insufficient number of teeth and limited supra-gingival tooth tissue. Where tooth borne anchorage is unavailable for significant orthodontic movement implants represent a viable alternative. This paper describes the use of dental implants for orthodontic anchorage in a partially dentate patient with a severe unilateral cross-bite where orthognathic surgery was the only other realistic option. The implants were successfully engaged using a composite bridge and a modified quad helix appliance for correction of the malocclusion. Once orthodontics was completed the patient was restored using highly sintered ceramic crowns and bridges. This paper highlights the importance of the multi-disciplinary team and the close liaison between the restorative dentist, orthodontist and technician in treatment planning and provision.

A comparison of plaster, digital and reconstructed study model accuracy.

OBJECTIVES: To evaluate the accuracy and reproducibility of a three-dimensional (3D) optical laser-scanning device to record the surface detail of plaster study models. To determine the accuracy of physical model replicas constructed from the 3D digital files. DESIGN AND SETTING: A method comparison study using 30 dental study models held in the Orthodontic Department, School of Dentistry, Cardiff University. MATERIALS AND METHODS: Each model was captured three-dimensionally, using a commercially available Minolta VIVID 900 non-contact 3D surface laser scanner (Konica Minolta Inc., Tokyo, Japan), a rotary stage and Easy3DScan integrating software (TowerGraphics, Lucca, Italy). Linear measurements were recorded between landmarks, directly on each of the plaster models and indirectly on the 3D digital surface models, on two separate occasions by a single examiner. Physical replicas of two digital models were also reconstructed from their scanned data files, using a rapid prototyping (RP) manufacturing process, and directly evaluated for dimensional accuracy. RESULTS: The mean difference between measurements made directly on the plaster models and those made on the 3D digital surface models was 0.14 mm, and was not statistically significant (P = 0.237). The mean difference between measurements made on both the plaster and virtual models and those on the RP models, in the z plane was highly statistically significant (P <0.001). CONCLUSIONS: The Minolta VIVID 900 digitizer is a reliable device for capturing the surface detail of plaster study models three-dimensionally in a digital format but physical models of appropriate detail and accuracy cannot be reproduced from scanned data using the RP technique described.

Modern restorative management of patients with congenitally missing teeth: 4. The role of implants.

UNLABELLED: In this fourth and final paper on the management of patients with congenitally missing teeth, the use of dental implants is considered. This group of patients often provides unique challenges when implant reconstruction is considered. Often a multidisciplinary approach is required involving orthodontists, oral surgeons and restorative dentists. The use of dental implant systems is a rapidly developing area of dentistry and its implications on hypodontia are discussed. This paper identifies the problems associated with a congenital absence of teeth and addresses their management in relation to the use of implants. CLINICAL RELEVANCE: The use of dental implants in hypodontia patients should always be considered as a treatment option. These groups of patients, however, require careful planning, often of a multidisciplinary nature, so that the timing of the various treatment modalities is seamless.

Modern restorative management of patients with congenitally missing teeth: 3. Conventional restorative options and considerations.

Restoration of spaces in hypodontia patients needs to take into account many factors including, the number of missing teeth, the distribution of space, the size of the teeth, and the age of the patient. This paper considers adhesive and conventional bridgework, as well as removal alternatives for the restoration of spaces. The various merits of each are discussed, together with treatment planning considerations for such cases.

Is amelogenesis imperfecta an indication for renal examination?

BACKGROUND: The term 'amelogenesis imperfecta' (AI) describes a diverse group of hereditary conditions primarily affecting the quality and/or quantity of dental enamel. CASE REPORT: This paper describes a case in which hypoplastic AI with delayed/failure of eruption of the permanent teeth was shown to be associated with renal calcification. CONCLUSION: Given the importance of the renal involvement, the authors suggest that paediatric dentists consider referring all children with this dental phenotype for renal ultrasound examination.

Modern restorative management of patients with congenitally missing teeth: 1. Introduction, terminology and epidemiology.

The management of patients with congenitally missing teeth can be a challenge and, in many cases, requires multidisciplinary care. In this four-part series, a contemporary approach to managing this group of patients is discussed. This first paper examines the terminology, epidemiology and restorative challenges that such patients can exhibit.

The 3-dimensional construction of the average 11-year-old child face: a clinical evaluation and application.

PURPOSE: This article describes construction of the average face and its application in the clinical environment. SUBJECTS AND METHODS: A total of 72 children, mean age 11.8 years, were selected for the study. Laser-scanned images of the subjects were obtained under a reproducible and controlled environment with 2 Minolta Vivid 900 (Minolta, Osaka, Japan) optical laser-scanning devices assembled as a stereo pair. A set of left and right scanned images was taken for each subject and each scan took an average of 2.5 seconds. These scanned images were processed and merged to form a composite 3-dimensional soft tissue reproduction of the subjects using commercially-available reverse modeling software. The differences in facial morphology were measured using shell deviation color maps. The average face was used to compare differences between male and female groups and 3 subjects with craniofacial anomalies. RESULTS: The difference between the average male and female face was 0.460 +/- 0.353 mm. The areas of greatest deviation were at the zygomatic area and lower jaw line, with the males being more prominent. The results of the surface deviation between the subjects with craniofacial anomalies were significant. CONCLUSIONS: The construction of the average face provides an interesting perspective into measuring changes in groups of patients and also acts as a useful template for the comparison of craniofacial anomalies.

Modern restorative management of patients with congenitally missing teeth: 2. Orthodontic and restorative considerations.

Managing edentulous spaces in patients with congenitally missing teeth demands careful planning and, often, a multidisciplinary approach. Orthodontic tooth movement can be considered to close spaces as well as improve the distribution of available teeth. In this second paper, the advantages of a collaborative approach are discussed.

The effect of topical fluorides on decalcification in patients with fixed orthodontic appliances: a systematic review.

INTRODUCTION: Decalcification is a significant problem during fixed orthodontic treatment. Topical Fluorides can reduce or eliminate the problem, but the relative effectiveness of different treatments or combinations of topical fluoride preparations is unknown. This systematic review was undertaken to determine the effectiveness of topical fluoride preparations in preventing decalcification during fixed orthodontic treatment. METHODS: A wide search of published and unpublished material in any language was undertaken by using general and specialist databases; key dental journals were searched by hand. Predefined inclusion criteria based on objective outcome measures of decalcification, duration of treatment, presence of a comparison group, and study design were applied to determine study selection. Included studies were double extracted onto pre-designed data extraction sheets. RESULTS AND CONCLUSIONS: By screening titles and abstracts, we identified 143 articles; after the inclusion criteria were applied, 7 reports (of 6 studies) remained. Differences in the methodologies and reporting made statistical analysis impossible. However, the use of topical fluorides in addition to fluoride toothpaste reduced the incidence of decalcification in populations with both fluoridated and non-fluoridated water supplies. Different preparations and formats appear to decrease decalcification, but there was no evidence that any 1 method was superior. There was some evidence that the potency of fluoride preparations might be important.

Reliability of measuring facial morphology with a 3-dimensional laser scanning system.

INTRODUCTION: The purpose of this prospective clinical trial was to evaluate the reliability of a 3-dimensional facial scanning technique for the measurement of facial morphology. METHODS: A field study was conducted in 2 comprehensive schools in the South Wales region of the United Kingdom. Forty subjects, mean age 11 years 3 months, were analyzed for soft tissue changes at baseline (T1), within 3 minutes (T2), and 3 days later (T3) by using 2 commercially available Minolta Vivid 900 (Osaka, Japan) laser-scanning devices assembled as a stereo pair. Left and right images were merged to form the whole face, and these images were superimposed to assess the errors at T1 and T2, and T1 and T3. RESULTS: The results showed that premerged left and right mean shell deviations were 0.38 +/- 0.14 mm for scans at T1, 0.31 +/- 0.09 mm at T2, and 0.34 +/- 0.12 mm at T3. The mean differences of the merged composite face were 0.31 +/- 0.08 mm between T1 and T2, and 0.40 +/- 0.11 mm between T1 and T3. Paired t tests showed no significant difference between these groups (P > .05). Shell deviation facial maps of the merged scans showed that 90% of the created composite facial scans were within an error of 0.85 mm. CONCLUSIONS: Capturing the soft tissue morphology of the face with this technique is clinically reproducible within 3 minutes and 3 days of the initial records.

Management of obstructive sleep apnea in an edentulous patient with a mandibular advancement splint: a clinical report.

Literature on the treatment of obstructive sleep apnea in edentulous patients with a mandibular advancement splint is sparse. This clinical report describes a clinical and laboratory method of splint fabrication and discusses the rationale for its use.

The influence of cavity shape on the stresses in composite dental restorations: a finite element study.

Dental restoration adhering to the cavity exhibits fundamentally different load transfer mechanisms from non-adhering restorations. It is therefore questionable that traditional cavity designs are optimal from a purely mechanical point of view when working with composite materials. Drawing from general engineering experience, it can be hypothesised that smooth, well rounded designs with bevelled margins are superior. A finite element model is used in the present investigation to determine the stress field in four different cavity designs as it develops during the curing of the restoration. The results show that a significant reduction of the stress along the adhesive interface between the tooth and the restoration can be achieved through the use of a rounded cavity shape. They also show that the adoption of bevelled margins leads to a reduction of the stress concentration at this location. These results are confirmed by a set of experimental results published in the literature. It is concluded that adhering restorations will perform better from a mechanical point of view if an appropriate cavity shape is selected.