RU2766729C1 - Method for minimally invasive combined extension of upper jaw - Google Patents

Abstract

FIELD: medicine.SUBSTANCE: invention relates to medicine, namely to dentistry, and can be used in combined orthodontic-surgical treatment in patients with maxillary narrowing. Based on the CBCT data of the skull, anatomical landmarks are determined and a surgical template is made for performing a piezocorticotomy. Access is made, a prepared surgical template is applied, and a piezocorticotomy procedure is performed within the zygomaticoalveolar junction. Mucoperiosteal flap is put back in place with subsequent suturing. After the manipulation, the upper jaw dilation apparatus is activated according to the proposed protocol.EFFECT: method enables high-accuracy assessment of the anatomical structures of the upper jaw for its predictable expansion at the skeletal level, reducing the risk of complications in the patients with skeletal narrowing of the upper jaw in the period of permanent occlusion, and also provides low invasiveness and reduced time of piezocorticotomy due to accurate planning by conducting a CBCT examination and using a surgical template.1 cl, 7 dwg, 1 ex

Description

This method relates to the field of medicine, in particular to dentistry, and can be used in combined orthodontic-surgical treatment in patients with narrowing of the upper jaw to achieve expansion of the upper jaw at the skeletal level.

There is a way to expand the upper jaw. Method includes expansion of the maxilla in patients with narrowing and deformity of the maxilla based on the proposed analysis of the CBCT study of the skull, the method of expansion with a combination of laser corticotomy (fractional photothermolysis) and the protocol for activation and deactivation of the expansion screw of the orthodontic appliance. To do this, a procedure of laser corticotomy (fractional photothermolysis) is carried out in order to reduce bone density and accelerate the movement of teeth in a transversal direction. After fixing the apparatus for expanding the upper jaw, the patient undergoes a laser corticotomy (fractional photothermolysis) procedure using the iPlus laser, the GoldHanpiace tip, Tip-MX7 (Biolase, USA), then the patient is recommended to activate the expansion screw by 4 turns on the day of the procedure and 3 turns on the day of the procedure. day after the intervention for 10 days. The patient then needs to deactivate the constriction screw by 3 turns per day for 10 days. The essence of this protocol is the periodic stretching and compression of the sutures of the upper jaw. [Arsenina O.I., Popova N.V., Makhortova P.I., Popova A.V. - RU 2734053 C1 SPK A61C 7/00 (2020.05) 2020].

The disadvantages of the method:

- the absence of the use of other anatomical zones that cause resistance of the upper jaw during corticotomy.

Closest to the proposed is a method for the treatment of skeletal forms of the mesial ratio of the dentition in patients with completed facial growth. The method includes an increase in the dental arch of the upper jaw with its expansion and a reduction in the length of the dentition of the lower jaw. To do this, the upper dentition and the entire upper jaw are expanded along the mid-palatal suture by using a corticotomy and an expanding apparatus with bone fixation, and to reduce the length of the lower jaw dentition, the lower third molars are removed and the lower dentition is moved in the distal direction using microimplants, installed in the lateral parts of the alveolar part of the lower jaw and the use of a bracket system. The study includes the actual fixation. The expansion is performed using an apparatus with extra-osseous fixation of its own design after corticotomy of the upper jaw in the suture area and along the outer surface. Reducing the length of the lower dentition is carried out by its distal movement after preliminary preparation of the site by removing the lower third molars. [Fadeev R.A., Fadeeva M.R., Prozorova N.V. - RU 2689027 C1 IPC A61V 17/00 (2006.01) 2019].

The disadvantages of the method:

- the absence of the use of other anatomical zones that cause resistance of the upper jaw during corticotomy.

The technical result of this invention is to increase the efficiency of orthodontic treatment of patients with a narrowing of the upper jaw who have refused major surgical interventions. This method aims to achieve maxillary expansion at the skeletal level using a minimally invasive piezocorticotomy procedure in areas of maxillary resistance.

The method is carried out as follows. The analysis of the degree of narrowing of the upper jaw at the dentoalveolar level was carried out by comparing the models of the upper and lower dentitions. Normally, when comparing the jaws with the correct inclination of the longitudinal axes of the teeth in the occlusal plane: the mesio-buccal tubercles of the first molars of the upper jaw should be located in the intertubercular fissure of the molars of the lower jaw. The distal-buccal cusps of the maxillary molars should be in close contact with the distal-buccal cusps of the mandibular first molars and with the mesial slope of the buccal cusps of the mandibular second molars, which corresponds to the 1st key of occlusion proposed by Andrews in 1872. Also, the assessment of the degree of narrowing of the upper jaw was performed on the basis of CBCT of the skull in patients according to the following cephalometric parameters: NF - a line running parallel to the lower border of the cone-beam computed tomography image along the lower border of the nasal passages; HPE - a line running parallel to the lower border of the cone-beam computed tomography image at the level of the hard palate; BAB - a line passing at the level of the buccal alveolar ridge; EWr, EWl - width line of the outer dentoalveolar arch, passing along the surface between the closest points along the equator of the crowns of the posterior group of teeth; PFr, PFl - width line of the outer dentoalveolar arch, passing at the level between the deepest points of the longitudinal fissures of the lateral teeth; HPI - hard palate width; ArAl - width between the tops of the palatine roots of the lateral teeth; RAV - line passing at the level of the palatine alveolar ridge; PWr, PWl - width line of the internal dentoalveolar arch, passing through the most pronounced area of the palatal surface of the lateral group of teeth; BFr, BFl - the vertical axis of the tooth, passing through the region of the bifurcation of the roots and the deepest points of the longitudinal fissures of the lateral teeth; <MSP-BFr, <MSP-BF1 - the angle of inclination of their vertical axis to the sagittal plane. Piezocorticotomy is aimed at reducing the resistance of the bones of the facial skeleton to the action of orthodontic equipment in areas of increased bone tissue resistance in adult patients. The main place of resistance to the expansion of the upper jaw at the skeletal level is the alveolar-zygomatic buttress, however, with a combination of compact osteotomy in the area of the zygomatic-alveolar suture and an orthodontic apparatus aimed at expanding the median palatine suture, it shows the greatest effect of expanding the upper jaw.

Based on the CBCT data of the skull, the orthodontist, together with the dental surgeon, determines the anatomical landmarks for the future piezocorticotomy procedure. Piezocorticotomy is performed in the area of the zygomatic-alveolar junction, based on the individual characteristics of patients according to CBCT. The procedure is performed under infiltration anesthesia with a solution of "Ultracain D-S forte" (1:100,000). An incision is made along the transitional fold of the mucous membrane from the first premolar to the second molar of the upper jaw. Exfoliate the mucoperiosteal flap. A fabricated surgical template is applied to perform precise piezocorticotomy.

Using a device with a piezoelectric effect for generating ultrasonic vibrations in the range of 24000-29500 Hz with a modulation frequency of 10-60 Hz in the “BONE, D1” mode, standard OTS74 tip (saw-shaped tip with five teeth, 0.55 mm thick and 0 .75 mm and cut depth marks) an osteotomy of the cortical plate is performed. Piezocorticotomy is followed by copious irrigation with sterile saline. The surgical guide is removed to perform the piezocorticotomy. The mucoperiosteal flap is returned to its place with subsequent suturing. After the manipulation, the patient is recommended to activate the apparatus for expanding the upper jaw according to the proposed protocol. This method does not involve the use of any specific apparatus for expanding the upper jaw.

The advantages of the proposed method:

- the possibility of analyzing and evaluating anatomical structures (position of the upper and lower jaws, inclination of teeth, morphological features of the skull bones, structure and quality of bone tissue);

- high accuracy in the assessment of the anatomical structures of the upper jaw for predictable expansion of the upper jaw at the skeletal level;

- reducing the risk of complications in patients with skeletal narrowing of the upper jaw in the period of permanent occlusion due to precise planning of piezocorticotomy according to the surgical template;

- low invasiveness and reduced time for piezocorticotomy according to the surgical template, which is comfortable for the patient.

Clinical example 1

Patient K, age at the time of treatment: 20 years. The patient complained of malocclusion. On the basis of clinical examination (Fig. 1) and CBCT examination (Fig. 2), the following diagnosis was made: skeletal form of jaw deformity, upper retromicrognathia, lower promacrognathia, mesial palatocclusion of molars; mesial palatocclusion of molars; sagittal reverse disocclusion of incisors, canines, premolars on the right; narrowing, deformation of the dentoalveolar arches; crowded position of the teeth of the upper and lower jaws; retrusion of the lower incisors, canines; chipped cutting edges of incisors. Adentia 3.5. Preserved 7.5. Anomaly in the position of primordia 2.8, 3.8, 4.8. Thin gum biotype.

After a diagnostic examination and drawing up a treatment plan, the patient was offered a treatment method using the proposed method of minimally invasive combined expansion of the upper jaw, and the first stage was the installation of a device for rapid palatal expansion (Fig. 3). The patient was referred for a piezocorticotomy procedure, which was performed using a device with a piezoelectric effect to generate ultrasonic vibrations in the range of 24000-29500 Hz with a modulation frequency of 10-60 Hz in the “BONE, D1” mode, a standard OTS74 tip (a saw-shaped tip with five teeth, 0.55 mm and 0.75 mm thick and saw cut depth marks) in the area of transition of the zygomatic bone to the upper jaw at the level from the second molars to the first premolars of the upper jaw (Fig. 4). After the procedure, the patient activated the expansion screw 3 turns per day after the intervention for 10 days. The patient then deactivated the constriction screw 3 turns per day for 10 days. The patient repeated the activation protocol 3 times. The total intensive expansion time was 8 weeks. Then, after 6 months of maintaining the achieved expansion, the apparatus was removed. In parallel with the expansion method, the patient was treated with a bracket system to normalize the position of the teeth, dentoalveolar arches and to achieve multiple fissure-tubercular contacts (Fig. 5). The patient was monitored dynamically, 8 months after active orthodontic treatment, a control examination was performed using cone-beam computed tomography (Fig. 6). We observed the dynamics of bone density decrease after piezocorticotomy according to the data of cone-beam computed tomography in the viewing program by conventional units.

The given data, respectively, reflect the values of the studied parameters at the time of the diagnostic and follow-up examinations.

Before treatment, the narrowing of the upper jaw in the area of the first molars corresponded to: NF - 63.87 mm - a line running parallel to the lower border of the CVT image along the lower border of the nasal passages; HPE - 57.51 mm - a line running parallel to the lower border of the CBCT image at the level of the hard palate; BAB - 54.03 mm - a line passing at the level of the buccal alveolar ridge; EWr, EWl - 50.94 mm - the line of the width of the outer dentoalveolar arch, passing along the surface between the most pronounced points along the equator of the crowns of the lateral group of teeth; PFr, PFl - 42.24 mm - the line of the width of the outer dentoalveolar arch, passing at the level between the deepest points of the longitudinal fissures of the lateral teeth. The inner width of the upper jaw: HPI - 27.98 mm - the width of the hard palate; ArAl - 40.36 mm - the width between the tops of the palatine roots of the lateral teeth; RAV - 29.82 mm - a line passing at the level of the palatine alveolar crest; PWr, PWl - 30.87 mm - the width line of the internal dentoalveolar arch, passing through the most pronounced area of the palatine surface of the lateral group of teeth; <MSP-BFr - 85°, <MSP-BFl - 93° - the angle of inclination of the vertical axis of the first molars to the sagittal plane.

After the treatment, the anatomical and functional balance in the maxillofacial region was restored due to the expansion of the upper jaw and the expansion of the upper jaw was achieved, which was measured by the same parameters:

The expansion in the area of the first molars became: NF - 64.01 mm; NRB - 64.17 mm; VAB - 61.76 mm; EWr, EWl - 61.57 mm; PFr, PFl - 51.46 mm; HPI - 35.03 mm; ArAl -48.97 mm; RAV - 38.37 mm; PWr, PWl - 39.41 mm; <MSP-BFr - 93°, <MSP-BFl - 94°.

After 16 months of active orthodontic treatment, the following changes occurred at the level of the first molars: the distance passing at the level of the buccal alveolar ridge increased by 7.73 mm; the distance passing along the surface between the most pronounced points along the equator of the molar crowns increased by 10.63 mm; , passing at the level between the deepest points of the longitudinal fissures of the lateral teeth increased by 9.22 mm, the width of the hard palate increased by 7.05 mm, the distance between the tops of the palatine roots increased by 8.61 mm, the distance passing at the level of the palatine alveolar crest increased by 8.55 mm, the width of the internal dental alveolar arch, passing through the most pronounced area of the palatal surface, increased by 8.54 mm, the angle of inclination of the vertical axis of the tooth 1.6 to the sagittal plane increased by 8°, the angle of inclination of the vertical axis of the tooth 2.6 to the sagittal plane increased by 1°. Those. Achieved normalization of occlusion transversely (Fig. 7).

This method was used to treat 20 patients aged 18 to 40 years.

Claims (1)

A method for orthodontic-surgical treatment of patients with narrowing of the upper jaw, including performing computed tomography of the maxillofacial area, on the basis of which a template with landmarks for piezocorticotomy is made, and installation of a device for rapid palatal expansion, then an incision is made along the transitional mucosal fold from the first premolar up to the second molar of the upper jaw, the mucoperiosteal flap is peeled off and the fabricated surgical template is applied, then a piezocorticotomy is performed in the area of the zygomatic-alveolar junction, the surgical template is removed to perform the piezocorticotomy, the mucoperiosteal flap is returned to its place with subsequent suturing, after the procedure, the device screw is activated for rapid palatal expansion to expand 3 turns per day for 10 days, then deactivate the screw to narrow 3 turns per day for 10 days, these procedures are performed 3 times with a total time of intensive of expansion for 8 weeks, then after 6 months of maintaining the achieved expansion, the apparatus is removed.

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