Gabriella Galluccio

Genetic basis of non-syndromic anomalies of human tooth number

Teeth organogenesis develops through a well-ordered series of inductive events involving genes and BMP, FGF, SHH and WNT represent the main signalling pathways that regulate epithelial-mesenchymal interactions. Moreover, progress in genetics and molecular biology indicates that more than 300 genes are involved in different phases of teeth development. Mutations in genes involved in odontogenesis are responsible for many dental anomalies, including a number of dental anomalies that can be associated with other systemic skeletal or organic manifestations (syndromic dental anomalies) or not (non-syndromic dental anomalies). The knowledge of the genetic development mechanisms of the latter is of major interest. Understanding the mechanisms of pathogenesis of non-syndromic teeth anomalies would also clarify the role of teeth in craniofacial development, and this would represent an important contribution to the diagnosis, treatment and prognosis of congenital malformations, and the eventual association to other severe diseases. Future research in this area is likely to lead to the development of tests for doctors to formulate an early diagnosis of these anomalies.

Impaction of permanent mandibular second molar: A retrospective study

Objective: To determine the prevalence of impacted mandibular second molar (MM2) and the association between MM2 impaction and crowding. The clinical significance of the angle between first and second mandibular molar and of the space between the first mandibular molar (MM1) and the anterior margin of mandibular ramus in MM2 impaction were also evaluated. Material and Methods: In this retrospective study , from the dental records of 2,945 caucasian young orthodontics patients, 40 subjects with MM2 impaction were included in a study group (SG) and compared with a control group (CG) of 200 subjects without MM2 impactions. The crowding, the angle of inclination of MM2, the distance between MM1 and mandibular ramus, the canine and molar relationships, and the lower centre line discrepancy were measured. For the statistical analysis , descriptive statistics and t-Student for independent sample groups were used. Results: The prevalence of impacted MM2 was 1.36%. The independent-Samples t-Test between SG and CG showed: the presence of crowding (P≤0.001), an higher angle values of MM2 inclination (P≤0.001) and a smaller distance between MM1 and the anterior margin of mandibular ramus (P≤0.001) in the SG. Conclusion: The impaction of MM2 is a relatively rare occurrence in orthodontic caucasian populations. The crowding, a higher angle values of MM2 inclination and a reduced distance between MM1 and the anterior margin of mandibular ramus, at the time of one third of MM2 root formation (T1), characterize MM2 impaction. Key words:Impacted mandibular second molar, impaction, orthodontics.

Craniofacial asymmetry in non-syndromic orthodontic subjects: clinical and postural evaluation.

Objective: The aim of this study was to evaluate the possible influence of a malocclusion pattern on a patient’s posture. Methods: Patients affected by symmetric malocclusion or malocclusion with mild to moderate non-syndromic craniofacial asymmetry were submitted to a clinical and X-ray evaluation. Subjects with symmetric skeletal class I were used as the control group. Evaluation of differences in postural pattern was performed using rasterstereography. Results: Statistical analysis (t-test) was performed on 61 patients divided in homogeneous subgroups. The results show a pelvic torsion angle of 1.08° + 3.00° (P = 0.0023) (normal value (NV) = 0.0–1.9°) in subjects presenting skeletal class II z asymmetry (control group: 1.17° ± 1.25°, not significant (NS)). Conclusions: The present study shows evidence of a relationship between malocclusion and spinal posture. A better understanding of the relationship between malocclusion and posture may help in planning a multidisciplinary approach that could involve other specialists.

The Association between Ponticulus Posticus and Dental Agenesis: A Retrospective Study

Objective: Neural tube defects may increase the risk of an abnormal development of skull, vertebral column and teeth formation, including dental agenesis in non syndromic patients. The association between the presence of a congenital Dental Agenesis (DA) and the Atlantooccipital Ligament (AOL) calcification, known as “Ponticulus Posticus” (PP), as possible links can be investigated. Design: After a systematic review of the scientific literature on this topic, two independent examiners assessed the AOL calcification in lateral cephalograms of 350 non syndromic patients(7-21 years old). The results were compared with a control group (non syndromic patients, without congenital missing teeth). Results: The 16.3% of the population studied by cephalometric analysis revealed a prevalence rate of PP (both complete and partial) with a slight male predominance is seen, not statistically significant (χ square test = 0.09; p= 0.76). In both sexes complete PP is more observed. In the patients affected by DA the frequency of PP is the 66.6% (both complete than partial). The χ square test with Yates correction showed a significative difference(χ= 66.20; p value= 0.00) between PP in patients with DA compared to not affected by DA. Conclusions: PP is not an uncommon anomaly. Since orofacial pain like migraine and other symptoms are often associated to PP, during routine radiographic examination, if detected, it should be documented in patients’ health record and with symptoms, further investigation should be sought for. These findings encourage to think there’s an association between DA in non syndromic patients and neuro-crestal cells defects.

Unilateral hemimandibular hyperactivity: Clinical features of a population of 128 patients

PURPOSE Facial asymmetries due to unilateral condylar hyperactivity are often a challenge both for maxillo-facial surgeons and for orthodontists; the current literature shows different opinions about aetiology, classification, treatment approach and timing. We made a retrospective study on patients suffering from unilateral condylar hyperactivity between 1997 and 2015 in our Department; clinical features and treatment options were grouped and compared with literature. METHODS The descriptive analysis investigated variables like sex, age, side and direction of the asymmetry, condylar activity and type of intervention. RESULTS The population was composed of 128 patients. The hemimandibular hyperactivity occurs equally in both sexes around the second decade, although the range of the first consultation goes from 7 to 49 y.o. The vertical hyperdevelopment group is almost equal to the horizontal. All the patients with horizontal hyperactivity showed negative scintigraphy and were treated with pre-surgical orthodontics and orthognathic surgery; patients with vertical hyperactivity and positive scintigraphy were treated with condylectomy and post-surgical orthodontics. CONCLUSION In our group of patients, direction of the hyperactivity and results of the scintigraphy lead to treatment choice and timing. Further studies are necessary to explain why, in our group, all the patients with horizontal involvement are negative to scintigraphy.

Delayed Eruption of Permanent Dentition and Maxillary Contraction in Patients with Cleidocranial Dysplasia: Review and Report of a Family

Introduction Cleidocranial dysplasia (CCD) is an inherited disease caused by mutations in the RUNX2 gene on chromosome 6p21. This pathology, autosomal dominant or caused by a spontaneous genetic mutation, is present in one in one million individuals, with complete penetrance and widely variable expressivity. Aim To identify the incidence of these clinical findings in the report of the literature by means of PubMed interface from 2002 to 2015, with the related keywords. The report of local patients presents a clinical example, related to the therapeutic approach. Results and Discussions The PubMed research resulted in 122 articles. All the typical signs were reported in all presented cases. The maxilla was hypoplastic in 94% of the patients. Missing of permanent teeth was found in two cases: one case presented a class II jaw relationship, instead of class III malocclusion. Similar findings were present in our cohort. Conclusion CCD is challenging for both the dental team and the patient. The treatment requires a multidisciplinary approach. Further studies are required to better understand the cause of this disease. According to this review, a multistep approach enhances the possibilities to achieve the recovery of the most possible number of teeth, as such to obtain a good occlusion and a better aesthetic.