Lucia Giannini

Sagittal and vertical effects of rapid maxillary expansion in Class I, II, and III occlusions

OBJECTIVE To evaluate and compare the skeletal vertical and sagittal effects of the Hyrax expander in Class I, II, and III patients. MATERIALS AND METHODS One hundred and eighty-three patients (91 females, 92 males) with a mean age of 8.7 years and with maxillary bilateral cross-bite and maxillary hypoplasia were analyzed retrospectively. They were divided into three groups according to their skeletal class. Sixty-five patients were skeletal Class I, 55 were skeletal Class II, and 63 were skeletal Class III. For each patient a lateral cephalogram was obtained before treatment and at the end of the retention period. Changes in the groups during the observation period were calculated, compared, and statistically analyzed with a t-test. RESULTS In terms of vertical effects, a statistically significant increase in the anterior vertical dimension was observed only in Class III patients. No statistically significant changes were observed in the posterior vertical dimension in any of the groups. In terms of sagittal effects, in Class I patients the maxilla and the mandible moved forward, but not in a statistically significant way, and the ANB angle showed a statistically significant decrease, but its change was less modified. In Class II patients the maxilla moved forward, but not in a statistically significant way, while the mandible moved forward in all of the patients in a statistically significant manner. The ANB decreased, statistically improving the skeletal classification. In Class III patients the maxilla moved forward in a statistically significant manner; the mandible showed a downward and backward rotation, improving the skeletal classification. CONCLUSIONS The data obtained in this study permit us to confirm that rapid maxillary expansion can be used in all of the skeletal classes with good vertical and sagittal results.

Long‐term results of early condylar fracture correction: case report

Condylar fractures in childhood occur frequently, often with minimal pain and discomfort and therefore the diagnosis is not made at the time of injury. Management may be surgical or non-surgical. Non-surgical therapy in children is the method of choice if the condyle can translate normally. In fact, there is an excellent chance of regeneration and continued normal development after fracture in growing patients. The purpose of this article is to describe the long-term clinical and radiological evaluation of a conservatively treated unilateral condylar fracture, a result of trauma, in a 6-year-old patient. In addition, she presented a congenitally missing lower incisor ipsilateral to the fracture and a class II malocclusion. She was treated with functional jaw orthopedics using a splint and an activator and subsequent orthodontic treatment with fixed appliances [J Orofac Orthop5 (2002) 429]. The remodeling process of the condylar head and neck is clearly observed in the panoramic radiographs of the 12-year follow-up records presented.

Orthodontic-surgical treatment: neuromuscular evaluation in skeletal Class II and Class III patients.

OBJECTIVES The aim of this study was the evaluation of the neuromuscular response to treatment according to diagnostic phases, as a follow-up of patients under surgical orthodontic treatment. The patient sample was subdivided into sub-samples, according to clinical characteristics. MATERIALS AND METHODS All of the patients who underwent orthognathic surgery in the Department of Orthodontics (University of Milan) were subjected to periodic electromyographic evaluation of the masticatory muscles (masseter and anterior temporal muscles), and to electrokinesiographic evaluation of the mandibular movements. The patient sample comprised 80 patients (37 males; and 43 females) at the end of growth. The electromyographic instruments used in the study included a Freely and a K6-I electromyography. Statistical evaluation was carried out with the Students t-tests for independent samples. RESULTS There are many differences between the skeletal Class II and skeletal Class III patients that are shown through the analysis of these data obtained. In the beginning phases of the treatment the muscular activities were higher in the Class II patients than in the Class III patients. Nevertheless this difference was reversed at the end of the treatment. A similar difference could be found in the mandibular kinesiology, in fact the maximum mandibular opening movement was greater in the skeletal Class II patients than in the skeletal Class III patients at the beginning of the treatment. At the end of the treatment this difference was lost. At the beginning of the treatment the Class II patients showed a greater protrusive movement of the mandibular than the Class III patients. At the end the treatment however this gap was reduced without being reversed. CONCLUSIONS Functional evaluation in patients in surgical orthodontic therapy is an important element in the diagnostic-therapeutic recordings, so as to reduce as much as possible any incorrect neuromuscular activity that can result in relapse.

Rapid maxillary expansion in growing patients. Hyrax versus transverse sagittal maxillary expander: a cephalometric investigation

The aim of this retrospective study was to cephalometrically evaluate and compare the skeletal and dental effects of a transverse sagittal maxillary expander (TSME) and a Hyrax-type expander (RME) in children with maxillary hypoplasia. Fifty subjects (26 males and 24 females), aged from 6 to 15 years, with a maxillary crossbite caused by basal apical narrowness, were divided into two equal groups. Twenty-five were treated with a TSME and the other 25 with a RME. For each patient, a lateral cephalogram was obtained before treatment (T0) and at the end of the retention period (T1). Changes in the two groups during the observation period were calculated, compared, and statistically analysed with a paired samples t -test. In the TSME group, SNP-A, I SN, and I FH and in the RME group SN-SNP.SNA, N-Me, and U6.PP displayed a statistically significant increase (P < 0.05). The increase in SNP-A, I SN, and I FH in the TSME group was significantly greater following treatment than in the RME group. The results support the use of the TSME to produce skeletal changes and dentoalveolar modification and to correct maxillary hypoplasia. It was also demonstrated that in patients with an anterior open bite, the use of the TSME is not contraindicated as the anterior vertical dimension did not increase significantly.

Orthodontic-surgical treatment: neuromuscular evaluation in open and deep skeletal bite patients

BackgroundThe aim of this study was to compare electromyographic data of two groups of patients (open and deep skeletal bite) before and after surgical orthodontic treatment.MethodsAll patients who underwent orthognathic surgery at the Department of Orthodontics (University of Milan) were subjected to periodic electromyographic evaluation of the masticatory muscles (masseter and anterior temporal muscles) and to electrokinesiographic evaluation of mandibular movements. The sample comprised 72 patients (35 open skeletal bite patients and 37 deep skeletal bite patients) at the end of craniofacial growth. The electromyographic instruments used in the study included a Freely and a K6-I electromyograph. Statistical evaluation was carried out with Student’s t tests for independent samples.ResultsLots of differences between open and deep skeletal bite patients have been underlined by the analysis of the electromyographic data obtained. These results have been obtained with both electromyographic systems. Muscular activity in microvolts is higher in deep skeletal bite patients at the beginning of the treatment than in open bite ones, but during the following phases of the treatment, the two values became similar.ConclusionsMorphologic differences between open and deep bite patients can also be demonstrated by instrumental examinations, and their correction after surgical treatment is observable on electromyographic and electrognatographic exams.

Presurgical orthodontic planning: predictability.

AbstractThe success of orthognathic surgery depends upon the anatomical details of the patient, the direction and extent of the necessary displacement, the experience of the surgical and orthodontic team, and the precision of presurgical orthodontic planning. The authors describe an experimental protocol to optimize presurgical orthodontic planning by the study of linear and rotational discrepancies of skeletal structures. Rotational changes of the skeletal structures can result in an overestimation or underestimation of linear discrepancies. Moreover, teeth can interfere with rotational movements, complicating presurgical planning.The study sample was a group of 20 adult patients, 7 males and 13 females. The inclusion criterion was adult patients who required correction of skeletal asymmetric class II or III malocclusion by osteotomy. Movements in the horizontal, frontal, and midsagittal planes can be simulated and measured through model surgery after diagnostic wax-up of the orthodontic treatment objective. Orthodontic presurgical preparation can be verified through the use of an occlusal splint, which represents a reliable guide during orthodontic preparation. The presurgical orthodontic phase can be obtained in less time and with more accuracy using this treatment planning method and indirect bonding of the orthodontic appliances.

Occlus-o-Guide®versus Andresen activator appliance: neuromuscular evaluation

BackgroundThe aim of the present study was to assess the muscular variations at the electromyography (EMG) level for the anterior temporalis muscles and masseter muscles during treatment with Occlus-o-Guide® and Andresen activator appliances.MethodsEighty-two patients (35 males and 47 females) aged between 8 and 12 years (mean age, 10.5 ± 0.8 years) participated in the study. Fifty patients underwent treatment with an Occlus-o-Guide® and 32 patients with an Andresen activator. All patients underwent EMG examination using a Freely EMG (De Gotzen, Legnano, Italy) and surface bipolar electrodes when the appliances were worn for the first time (T0), and after 6 months (T1) and after 12 months (T2) of appliance use.ResultsStatistical analysis showed that both at T0 and T2, the percent overlapping coefficient (POC) of the anterior temporalis muscles was not statistically different between the appliance groups. At T0, the POC of the masseter muscles was significantly lower for the Andresen appliance as compared to the Occlus-o-Guide® (p = 0.02), while at T2 this significance was lost.ConclusionsAt insertion of an appliance, all patients show neuromuscular balance that does not correspond to orthognathic occlusion. Both appliances work by creating muscular imbalance. With the appliances in situ, EMG responses were generally analogous for the Occlus-o-Guide® and the Andresen activator; however, the imbalance was greater and the recovery of the orthological muscular balance was slower in patients under treatment with the Andresen activator as compared to those with the Occlus-o-Guide®.

A 5-year longitudinal study of survival rate and periodontal parameter changes at sites of dilacerated maxillary central incisors

BackgroundAlthough dental dilaceration disinclusion is an accepted treatment modality, few studies have evaluated the prognosis for dilacerated maxillary incisors and changes in clinical periodontal parameters still need to be demonstrated. The objectives of this study were to evaluate the prognosis and changes in clinical attachment level (CAL), probing depth (PD), and soft tissue recession (REC) for disincluded dilacerated maxillary incisors.MethodsTen impacted dilacerated teeth were scheduled for disinclusion. Five of them were disincluded with the apically repositioned flap technique and the other five with the closed eruption technique and brought into alignment with light orthodontic forces.ResultsAll the dilacerated teeth were disincluded as planned. CAL, PD, and REC were the same as natural teeth. Among the two surgical techniques, no statistically significant differences have been found.ConclusionThe choice to disinclude dilacerated central maxillary incisors reached the goals planned. Periodontal parameters obtained in a short- and long-term follow-up allow to affirm that the disinclusion of dilacerated teeth has a good survival rate.

Menopause: Changes in the Mouth Cavity and Preventive Strategies

Aim:Menopause is a term used to describe the permanent cessation of the primary functions of the human ovaries. Menopause typically occurs in women in midlife and signals the end of the fertile phase of a woman’s life. The transition from reproductive to non-reproductive is the result of a major reduction in female hormonal production by the ovaries. During the menopause remarkable changes happen in the mouth cavity as osteoporosis, periodontal disease, Burning Mouth Syndrome (BMS) and xerostomia. The aim of this work is to describe the changes that occur during the menopause in the mouth cavity and the preventive protocols used in the Preventive Dental Department of the University of Milan. Material and Methods: A systematic literature review about the menopause and its modifications in the mouth cavity have been made using the data base Medline and key words as “oral health” and “menopause” have been searched. Discussion and Conclusions:Different changes in women oral condition can be observed during menopause.These pathological conditions are typical of the hormonal phase and they must be known by clinicians in order to make a correct intervention. Problems as osteoporosis, periodontal disease, Burning mouth syndrome and xerostomia could be prevented using specific protocols.

Presurgical virtual three-dimensional treatment planning.

Aim:This article describes an experimental protocol designed to optimize surgical orthodontic diagnosis and treatment plan. Materials and Methods:In this study, 15 patients undergoing orthodontic-surgical treatment have been analyzed.The superimposition between models and respective presurgical setup for each group was performed. A best-fit algorithm was used to find the position of the arches in space for which the sum of the discrepancies was the shortest.A punctual variation colorimetric map indicating percentages of areas subjected to different discrepancies was used to evaluate the degree of congruence between the 2 models.Furthermore, for each arch the software provided metric values of maximum positive deviation, maximum negative deviation, mean deviation, and standard deviation that characterize the points compared in the superimposition. Results:For all the considered patients, the orthodontic preparation for surgery was obtained according to the splint guides and the orthodontic planning. Conclusion:The protocol described here allows high-precision planning of orthodontic-surgical therapy optimization of each treatment phase, with consequent advantages in clinical practice.