Golden Mean and Proportion in Dental Esthetics after Orthodontic Treatments: An In Vivo Study.

PURPOSE: The definition of the golden ratio was established around the sixth century BC; Levin and Snow developed specific theories applicable in dentistry, which apply the golden proportion rule with the intention of reproducing a perfect smile. This study analyzed the literature and assessed whether these concepts remain valid and applicable in clinical practice, evaluating the theories with a group of patients followed by an experienced orthodontic team. METHODS: This study was retrospectively performed on 400 patients (241 females and 159 males) who underwent orthodontic treatments. The analysis was conducted on intraoral frontal photos, both pre-treatment and post-orthodontic treatment, to observe if there was a statistically significant difference in the tooth display according to the golden mean and golden proportion theories. RESULTS: The canine at the end of the orthodontic treatment had a greater visibility than that proposed by Levin and Snow. CONCLUSIONS: This study revealed how these theories could be considered in certain respects, but nowadays are not totally valid and applicable to the clinical reality. Snow's theory appears to be more consistent with the clinical findings than Levin's theory.

Oral Manifestations and Maxillo-Facial Features in the Acromegalic Patient: A Literature Review.

Background: Acromegaly is a chronic disease caused by an abnormal secretion of growth hormone (GH) by a pituitary adenoma, resulting in an increased circulating concentration of insulin-like growth factor 1 (IGF-1). The main characteristics are a slow progression of signs and symptoms, with multisystemic involvement, leading to acral overgrowth, progressive somatic changes, and a complex range of comorbidities. Most of these comorbidities can be controlled with treatment. The literature reveals that the most evident and early signs are those related to soft tissue thickening and skeletal growth, especially in the head and neck region. Methods: The authors reviewed the available literature on the clinical oro-dental features of acromegaly, selecting articles from PubMed and Google Scholar. The aim of this review was to summarize all the reported clinical oro-dental features of acromegalic patients. Results: The most common facial dimorphisms involved the maxillo-facial district, with hypertrophy of the paranasal sinuses, thickening of the frontal bones, and protruding glabella, which may be associated with joint pain and clicks. Regarding the oro-dental signs, the most frequent are dental diastema (40-43%), mandibular overgrowth (22-24%), mandibular prognathism (20-22%), and macroglossia (54-58%). These signs of acromegaly can be significantly reduced with adequate treatment, which is more effective when initiated early. Conclusions: Increased awareness of acromegaly among dentists and maxillo-facial surgeons, along with the early identification of oro-facial changes, could lead to an earlier diagnosis and treatment, thereby improving patients' quality of life and prognosis.

The role of the dentist and orthodontist in recognizing oro-facial manifestations of acromegaly: a questionnaire-based study.

PURPOSE: Oro-facial manifestations of acromegaly are among the earliest signs of the disease and are reported by a significant number of patients at diagnosis. Despite this high prevalence of acromegaly oral manifestation, dentists do not play a pivotal role in acromegaly identification and diagnosis. The aim of our study was to evaluate the ability of dentists and orthodontists in the early recognition of the oro-facial manifestations of acromegaly. METHODS: A telematic questionnaire was administered to dentists and orthodontists. The questionnaire included photos with facial and oral-dental details and lateral teleradiography of acromegaly patients (ACRO). RESULTS: The study included 426 participants: 220 dentists and 206 orthodontists. Upon reviewing the photos, dentists most often observed mandibular prognathism and lips projection, while orthodontists also reported the impairment of relative soft tissue. Orthodontists, who usually use photos to document patients' oral-facial characteristics, paid more attention to oral-facial impairment than dentists. During dental assessment, 90% of the participants usually evaluated tongue size and appearance, diastemas presence, and signs of sleep impairment (mainly orthodontists). Orthodontists were also more able to identify sella turcica enlargement at teleradiography. A total of 10.8% of the participants had ACRO as patients and 11.3% referred at least one patient for acromegaly suspicion. CONCLUSION: The study highlighted dentists' strategic role in identifying ACRO. Increasing dentists' awareness about acromegaly clinical issues may improve early diagnosis, potentially resulting in an increased quality of life and decreased mortality among ACRO.

Application of Nanotechnology in Orthodontic Materials: A State-of-the-Art Review.

Nanotechnology refers to the science that manipulates matter at molecular and atomic levels, and studies matter at the nanoscale level to detect and exploit the useful properties that derive from these dimensions; materials with components less than 100 nm in at least one dimension are called nanomaterials. Nanotechnology is applied in many fields, such as medicine (nanomedicine) and dentistry (nano-dentistry). The purpose of these innovations and research in this field is to improve human life and health. This article aims to summarize and describe what the most recent and known innovations of nanotechnology in dentistry are, focusing on and paying particular attention to the branch that is orthodontics, and on the application of new nanomaterials in the realization, for example, of orthodontic elastomeric ligatures, orthodontic power chains, and orthodontic miniscrews. We also address a very important topic in orthodontics, which is how to reduce the friction force.