Common variants of EDA are associated with non-syndromic hypodontia.

OBJECTIVE: The aim of this case-control study was to investigate the association between non-syndromic hypodontia and nineteen common variants of candidate genes ectodysplasin A (EDA), paired box 9 (PAX9), msh homeobox 1 (MSX1) and axis inhibition protein 2 (AXIN2). SETTINGS AND SAMPLE POPULATION: Sixty-one hypodontia cases were frequency-matched to 253 controls with no missing teeth (excluding the third molars). MATERIAL AND METHODS: Self-report data and DNA samples were collected from each participant. RESULTS: The sample had a mean age of 16.6 years (SD = 7.3), with most participants being female (59.6%), and of New Zealand European origin (75.4%). Using multiple logistic regression analysis, it was found that the T-allele of rs12853659 (EDA) and the G-allele of rs2428151 (EDA) were both associated with a higher risk of hypodontia (odds ratio, OR = 2.79, 95% CI = 1.11-7.01; and OR = 2.87, 95% CI = 1.04-7.94, respectively). The G-allele of rs2520378 (EDA) showed a protective effect with an OR of 0.61 (95% CI = 0.38-0.99). The EDA SNP findings were consistent with previous reports included in a meta-analysis. No associations were found with the PAX9, AXIN2 and MSX1 genes, after adjusting for sex and ethnicity. CONCLUSIONS: Common variants of the EDA genes are associated with specific phenotypes of non-syndromic hypodontia, thus confirming their role in the regulatory pathways of normal tooth development. However, larger samples are needed to investigate the association further.

Bone fill following secondary alveolar bone grafting for children with cleft of the alveolus in New Zealand.

OBJECTIVE: To investigate the amount of bone fill post-secondary alveolar bone grafting for children with cleft in New Zealand. SETTINGS AND SAMPLE POPULATION: Retrospective analysis of post-operative intra-oral periapical and upper anterior occlusal radiographs of 45 grafted sites where all grafting was undertaken within the New Zealand public hospital service. MATERIALS AND METHODS: A modified Kindelan Index and a 100 mm visual analogue scale (VAS) were used to assess the amount of bone fill using intra-oral radiographs by 4 orthodontists experienced in cleft care and who were blind to the patient's identity. Fourteen duplicated radiographs were randomly selected and added to the sample for reliability assessment. RESULTS: The Kindelan Index rated 37.8% Grade 1 (Good), 31.1% rated Grade 2 (Satisfactory), 22.2% rated Grade 3 (Unsatisfactory) and 8.9% Grade 4 (Failure), a combined unsatisfactory/failure rate of 31.1%. The average VAS score was 50 mm ± 24 mm, and there was a strong relationship between Kindelan and VAS assessments. Those patients aged 10-11 years had significantly better outcomes using both assessments compared to those aged <10 and >11. The VAS assessment found that higher caseload surgeons had better outcomes, although the difference was of borderline statistical significance (mean VAS 56 mm vs 44 mm P = 0.07). CONCLUSIONS: Contemporary secondary alveolar bone grafting bone fill outcomes in New Zealand are poor when compared to contemporary international studies. These findings indicate a review of secondary bone grafting is required to improve outcomes for New Zealand children with cleft.

Long-term changes in oral health-related quality of life of standard, cleft, and surgery patients after orthodontic treatment: A longitudinal study.

INTRODUCTION: The aim of this study was to assess long-term changes and describe the trajectories of oral health-related quality of life (OHRQoL) in a cohort of cleft, surgery, and standard patients who received orthodontic treatment. METHODS: Standard (n = 16), cleft (n = 19), and orthognathic surgery (n = 22) patients completed the short-form of the Oral Health Impact Profile (OHIP-14) before treatment, immediately posttreatment, and approximately 5 years posttreatment. RESULTS: An overall reduction in OHIP-14 scores (improvement in OHRQoL) occurred after orthodontic treatment; however, this was only significant for the surgery and standard groups (P <0.05). The total OHIP-14 score increased significantly from posttreatment to 5 years follow-up for all 3 study groups (P <0.05). Relative to pretreatment, however, there were significant reductions in total OHIP-14 scores at 5 years posttreatment in the surgery group (-57.4%; P <0.05), but not in the standard sample (-24.2%; P >0.05). By contrast, the OHIP-14 score in the cleft group increased but not significantly (40.2%; P >0.05). Using a mixed model analysis, a significant interaction was detected between patient group and time (ie, study time point) (F = 6.0; P <0.0001), after adjusting for age and sex. CONCLUSIONS: Distinct patient groups showed different OHRQoL trajectories after orthodontic treatment. Treatment-related improvements in OHRQoL are maintained over time for surgery patients, but not for those with standard malocclusions and orofacial clefts.

Comparison of Reliability of Categorical and Continuous Scales for Radiographic Assessments of Bone Infill Following Secondary Alveolar Bone Grafting.

OBJECTIVES: To investigate examiner reliability of scoring intraoral radiographs of bone infill following secondary bone grafting using a categorical scale (modified Kindelan Index) and a 10-cm visual analog scale (VAS). To investigate the level of clinical experience on the reliability of these assessments. DESIGN: Retrospective study involving 10 clinicians of varying clinical experience who were blind to the patient's identity. SETTING: All grafting was carried out within the New Zealand public hospital service. PATIENTS: Fifty-eight grafts (48 UCLP and 5 BCLP) were assessed with 14 duplicated radiographs randomly added to the sample, making a total of 72 radiographs for assessment. MAIN OUTCOME MEASURES: Weighted kappa was used for intra- and interrater examiner reliability for the categorical scale and correlations for the VAS. RESULTS: Relatively poor intrarater examiner agreement for categorical scoring (median 0.46) was found. Clinicians with greater experience generally recording higher intrarater weighted kappa. The intrarater correlations for the continuous scale (median 0.89) suggest better consistency regardless of the level of experience. The interrater relationships were generally low, with an average of weighted kappa of 0.25 while the overall average VAS correlation was 0.49. For the majority of scorers, there was a relationship between the VAS and the Kindelan Index, with lower VAS scores related to worse Kindelan scores. CONCLUSIONS: The use of a VAS produced better intra- and interexaminer reliability than the categorical Kindelan Index and was more consistent despite the level of clinical experience. Further evaluation of the validity of the VAS for the assessment of bone infill is warranted.

Hypodontia: An Update on Its Etiology, Classification, and Clinical Management.

Hypodontia, or tooth agenesis, is the most prevalent craniofacial malformation in humans. It may occur as part of a recognised genetic syndrome or as a nonsyndromic isolated trait. Excluding third molars, the reported prevalence of hypodontia ranges from 1.6 to 6.9%, depending on the population studied. Most affected individuals lack only one or two teeth, with permanent second premolars and upper lateral incisors the most likely to be missing. Both environmental and genetic factors are involved in the aetiology of hypodontia, with the latter playing a more significant role. Hypodontia individuals often present a significant clinical challenge for orthodontists because, in a number of cases, the treatment time is prolonged and the treatment outcome may be compromised. Hence, the identification of genetic and environmental factors may be particularly useful in the early prediction of this condition and the development of prevention strategies and novel treatments in the future.

Management of missing mandibular second premolars: a review.

Tooth agenesis is the most common developmental dental anomaly and it is frequently associated with other dento-skeletal disturbances, such as structural variations of other teeth, late dental eruption, transpositions and crowding. Except for the third molars, the mandibular second premolars are the most commonly missing teeth. Oral rehabilitation of patients with missing mandibular premolars often requires a multi-disciplinary approach, and usually results in prolonged treatment time and a greater burden of care. An understanding of the aetiology and clinical features of hypodlontia is essential for the planning phase and the outcome of treatment. The purpose of the present review is, therefore, to discuss the aetiology of hypodlontia as well as to evaluate the clinical options available for the treatment of missing mandibular second premolars. An insight into future research directions and their clinical applications will also be discussed.

An osteosclerotic form of Robinow syndrome.

Robinow syndrome (RS) is a clinically and genetically heterogenous condition primarily characterized by short stature, mesomelia, genital hypoplasia, oral abnormalities, and a facial gestalt that includes hypertelorism, a short nose, and a broad mouth. The disorder exists in both a dominant and a more severe recessive form. Here two unrelated cases of sporadic RS are described with the additional finding of axial and appendicular osteosclerosis. These two patients, coupled with three additional patients previously described in the literature, may represent a distinct sub-phenotype of this condition.

New Zealand dentists' use of gingival retraction techniques for fixed prosthodontics and implants.

OBJECTIVE: To identify the techniques most commonly used in New Zealand for gingival retraction for impressions of natural teeth and implants in fixed prosthodontics. DESIGN: Postal survey of a random sample of dentists METHODS: A questionnaire was mailed to all members of the New Zealand Dental Association (NZDA). Data were analysed using SPSS. RESULTS: The response rate was 51%. Veneer, crown and bridge treatments were routinely carried out by 89% of respondents, while implant treatment and/or implant-supported prostheses were provided by 65%. Around natural teeth, gingival retraction was mainly achieved with surgery (including electrosurgery, laser and rotary curettage) and/ or cord, by 82% of dentists. Cord with chemicals was used by 63% and plain cord by 37%. Gingival retraction around implants was used by 18%. Among the latter, the most popular gingival retraction method for use around implants was plain cord (used by 31%), while 25% used cord with chemicals. Another 23% reported using surgery as their means of gingival retraction around implants, while 19% reported using Expasyl (Pierre-Roland), and 2% reported using Magic Foam Cord (Dentsply), both of which are injectable matrices for gingival retraction. CONCLUSION: Dentists in New Zealand undertake a considerable amount of fixed prosthodontic and implant work. Gingival retraction around natural teeth is used commonly, while only a small number of participants report using it for implants. A surprising finding was the relatively high number of participants who reported using surgery for gingival retraction around natural teeth.