Quantitative investigation of the esthetic impact of lip prominence in relation to the esthetic line

Introduction The purpose of this quantitative investigation was to assess the influence of lip prominence in relation to the esthetic line (E-line) on perceived attractiveness and threshold values of desire for treatment. Methods The lip prominence of an idealized silhouette male white profile image was altered incrementally between −16 mm to 4 mm from the E-line. The images were rated on a Likert scale by pretreatment orthognathic patients (n = 75), laypeople (n = 75), and clinicians (n = 35). Results In terms of perceived attractiveness, lips to E-line distance within the ranges of −12 mm to −16 mm and 0-4 mm in relation to the E-line was associated with a reduction in median attractiveness scores to below 4 in the patient and clinician groups of observers; for the lay group, the corresponding ranges were −14 mm to −16 mm and 2-4 mm. Relative lip prominence appears to be viewed as more attractive than lip retrusion. Clinicians were generally least likely to suggest treatment for varying levels of bilabial position. For a number of the images, there was reasonable agreement among clinicians and laypeople regarding whether treatment is required. For the clinician group, the only categories for desire for treatment were at a lip to E-line distance within the ranges of −14 mm to −16 mm and 2-4 mm. Conclusions It is recommended that the range of normal variability of the prominence of the lips and threshold values of the desire for treatment be considered in planning

“Over-reviewing” of research? An analysis of orthodontic reviews

Introduction: Research overviews may be undertaken to identify gaps in the literature, evaluate existing systematic reviews (SRs), and summarize evidence. This paper aims to profile overviews that have been conducted in orthodontics and related interventions since 2012 and to evaluate the degree of overlap among these overviews. Methods: Overviews published between January 1, 2012 and June 20, 2023 were identified using an electronic search involving Google Scholar and PubMed. A descriptive summary was produced, and citation matrices were used to evaluate the percentage of overlap between overviews using corrected covered area and covered area. This was classified as slight, moderate, high, or very high. Results: A total of 35 overviews were identified across a wide range of topics. Eight overviews included 20 SRs (median no. of SRs per overview, 15; range, 3-62). Meta-analysis was conducted in only 5 overviews. Overlap between overviews on the same topic ranged from slight (2.7%) to very high (53.8%). Conclusions: Almost all overview topics address treatments and their effects, with a wide variation in the number and quality of SRs included. There is considerable overlap in some orthodontic overviews, suggesting unnecessary duplication and research waste. Researchers should be encouraged to focus on primary data collection to add more high-quality data to SRs, which will ultimately enhance the yield from secondary and tertiary orthodontic research

Impacted maxillary canines: contemporary management and review of the literature

Management of impacted maxillary canines forms a sizeable proportion of orthodontic treatment provided in dental school and district general hospital settings. Patients presenting with impacted canines fall into the highest category on the Index of Orthodontic Treatment Need (IOTN). Patients who agree to have surgical exposure and subsequent orthodontic alignment of an impacted canine are committing themselves to a course of treatment that could take up to three years, towards the end of which the patient's enthusiasm may be waning. Prevention, or at least early interception of the impacted canine, could save a protracted course of treatment and avert not only the surgical morbidity associated with exposure of the impacted tooth but also the general risks associated with orthodontic treatment. Esma J Doğramacı, Farhad B Nain

The long-term influence of orthodontic treatment on dental knowledge and behaviour: an Australian cohort study

Objectives: Fixed orthodontic treatment (FOT) typically lasts 14–33 months, with regular appointments at short intervals to monitor changes, adjust appliances, and remotivate patients to maintain excellent oral hygiene standards to prevent dental disease. Past experiences are important influencers of dental attitudes and self-care dental behaviours in adulthood. Since FOT comprises a high frequency of appointments compared to other dental visiting, we hypothesised that previous FOT enhances dental knowledge and behaviour in later life. Methods: This cohort study followed-up 30-year-old participants who originally took part in an oral epidemiological study when aged 13-years. Participants completed a questionnaire regarding sociodemographics, dental health behaviours, dental knowledge (prevention of caries and periodontal disease, including questions about popular myths) and FOT. Data analysis comprised un/adjusted binomial logistic regression and multivariate generalised linear regression. Results: Data for 448 participants (56 % female, 35 % received FOT) were analysed; adjusted models controlled for sociodemographics and baseline malocclusion severity. There was no association between FOT and regular toothbrushing (Exp B: 1.35, 95% CI: 0.87–2.10), flossing (Exp B: 1.18, 95 % CI: 0.48–2.90), dental attendance within last 2 years (Exp B: 0.96, 95 % CI: 0.62–1.49) or a non-emergency dental visit (Exp B: 1.01, 95 % CI: 0.51–1.99). Non-FOT participants placed importance on a calcium-rich diet preventing caries (Exp B: 1.99, 95 % CI: 1.14–3.50, P<0.05), while those with a baseline definite malocclusion had higher levels of knowledge about dental visiting compared to those with minimal or more severe malocclusions (P<0.05). Conclusion: Previous FOT appears to have limited impact on dental knowledge and may not affect long-term dental behaviours. Clinical significance: This 17-year follow-up study examined the influence of previous fixed orthodontic treatment on dental knowledge and behaviour later in life. Although patients have numerous and regular appointments during the course of orthodontic treatment, this does not seem to impact on either dental knowledge or behaviour in adulthood.Esma J. Doğramacı, Farhad B. Naini, David S. Brenna

Retrospective analysis of nasal soft tissue profile changes with maxillary surgery

Purpose: The aim of this study was to analyze the changes in the position of the nasal and labial soft tissue profile of patients undergoing bimaxillary orthognathic surgery, with special emphasis on the effect on the nasal tip projection. Materials and Methods: The lateral cephalometric radiographs of 27 consecutive patients (16 female and 11 male patients; mean age, 22 years) who had undergone maxillary advancement and mandibular setback were studied. The pretreatment and end-of-treatment lateral cephalometric radiographs were selected. The pretreatment and end-of-treatment radiographs were superimposed on the sella-nasion plane, and the case was only included if there had been no change in sella-nasion length (ie, no growth). Analyses of Pearson correlation coefficient and stepwise linear regression tests were used to compare the cephalometric measurements at the beginning and at the end of treatment. Paired-sample t tests were also performed to analyze changes in nasolabial angle (NLA) and columella-lobular angle (CLA). Results: The correlations between vertical movement of nasal tip, A-point, and maxillary incisal tip were important. Although there was an important correlation between nasal and incisal tip, interestingly, there was no correlation between nasal tip and A-point in horizontal movement. According to stepwise linear regression analysis, the best model for horizontal movement of nasal tip was as follows: Nasal anteroposterior movement = 0.241 + 0.188 × Incisal tip anteroposterior movement + 0.153 × Incisal tip superoinferior movement. For vertical movement of nasal tip, the best model was as follows: Nasal superoinferior movement = -1.117 + 0.399 × Incisal tip superoinferior movement + 0.323 × A-point anteroposterior movement. There was no significant relation in angular measurements of NLA and CLA before and after treatment. Conclusion: The results of our study suggest that both horizontal and vertical movements of nasal tip were related to incisal tip and A-point movements; however, angular changes in CLA and NLA did not affect the nasal tip. © 2011 American Association of Oral and Maxillofacial Surgeons