Defects and deformities of the palate: causes, symptoms, diagnosis, treatment

Defects of the palate can occur as a result of gunshot and non-gunshot injuries, inflammatory processes, as well as as a result of surgical removal of a tumor of the palate, previously unsuccessful uranostaphyloplasty, etc.

According to available data, postoperative defects and deformations of the palate remain in 1.8-75% of patients operated on for congenital non-fusion of the palate.

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What causes defects and deformities of the palate?

Among inflammatory processes, the most common causes of acquired deformations of the palate are syphilis, odontogenic osteomyelitis, and also necrosis of the palate due to the erroneous introduction of a solution that has the properties of a protoplasmic poison (alcohol, formalin, hydrogen peroxide, etc.).

A defect of the hard palate can also occur as a result of its irritation by a suction prosthesis, causing the appearance of a hematoma with subsequent inflammation of the mucous membrane, periosteum and bone with its sequestration.

In peacetime, a dentist most often encounters postoperative defects. Thus, in each maxillofacial clinic, a significant portion of patients still consists of people with defects and deformations that arose as a result of uranostaphyloplasty.

In our opinion, the following factors are the reasons for such frequent occurrence of postoperative through defects:

• stereotypical use of the same surgical method for different forms of non-fusion of the palate;
• failure to comply with the technique of rational operation;
• trauma to flaps separated from the hard palate with tweezers;
• too frequent placement of sutures on the palate;
• lack of plastic material in very wide and atypical non-unions;
• bleeding after surgery and associated tamponade of bleeding areas of the wound;
• insufficient retrotransposition and mesopharyngoconstriction (as a consequence of the restraining influence of the vascular-nerve bundles even if they are removed from the bone bed using the method of P. P. Lvov);
• use of a single-row suture when the edges of the crevice defect are not brought together freely enough, etc.

The causes of cicatricial deformation and shortening of the newly created soft palate after uranostaphyloplasty are the formation of coarse scars on the surface of the soft palate facing the nasal part of the pharynx in the peripharyngeal niches and interlaminar spaces (after interlaminar osteotomy).

The medial pterygoid plate returns to its original position under the influence of scars and the traction of the internal part of the medial pterygoid muscle, which is attached to this split off plate.

To a large extent, the formation of scar tissue in the peripharyngeal niches and interplate spaces is facilitated by tight tamponade with iodoform-gauze strips.

Symptoms of defects and deformations of the palate

Symptoms of through-and-through defects of the palate largely depend on their location, size and the presence of associated defects (lips, cheeks, nose, teeth, alveolar processes).

With isolated defects of the hard palate, patients complain of food (especially liquid) getting into the nose. The more extensive the defect of the palate, the worse the pronunciation. Some patients cover the defects with wax, plasticine, cotton wool, gauze, etc., to get rid of these painful symptoms.

If a defect of the hard palate is combined with a defect of the alveolar process and lip, complaints of facial disfigurement and difficulty in grasping and holding food in the mouth are added.

In the absence of a sufficient number of supporting teeth, patients complain of poor fixation of the upper removable denture; complete removable dentures are not retained on the upper jaw at all.

Large through defects of the soft palate and in the area of its border with the hard palate always affect the clarity of speech and lead to food entering the nasal part of the pharynx, causing chronic inflammation of the mucous membrane there.

Small (pinpoint or slit-like) defects of the soft palate may not be accompanied by subjective disorders, but food still leaks through them into the nasal part of the pharynx, as with narrow slit-like defects of the hard palate.

It has been noted that patients with deformation of the dental and jaw system suffer from caries 2-3 times more often.

Cicatricial deformations and shortening of the soft palate are accompanied by pronounced speech disorders (open nasality), which cannot be eliminated by any conservative means.

The change in the facial profile of patients most often occurs as a result of the predominance of the lower lip over the upper. This deviation is most pronounced in individuals who have previously undergone surgery for through forms of non-fusion of the palate.

The main type of deformation of the upper dental arch is its narrowing, especially in the area of premolars, and underdevelopment along the sagittal axis. These changes are most pronounced in patients who have undergone surgery with through forms of non-union of the palate and a permanent bite. Pronounced deformations of the bite are observed in patients with through forms of non-union of the palate who have previously undergone surgery on the palate. They have false frontal progenia, which occurs as a result of underdevelopment of the upper jaw along the sagittal axis, and unilateral or bilateral crossbite as a result of its narrowing.

Teleroentgenography data confirm that in patients with through forms of nonunion of the palate, the basal part of the upper jaw is underdeveloped. The cause of underdevelopment of the upper dental arch along the sagittal axis is the pressure of the cicatricial upper lip and, possibly, interlaminar osteotomy, which is performed in the pterygomaxillary growth zone of the upper jaw along the sagittal axis.

Patients with traumatic defects of the palate who suffer from speech disorders are depressed by the fact that people around them suspect that they have a defect of syphilitic origin. This is one of the factors that motivate them to seek treatment.

To the characteristics of acquired defects of the palate, largely reflected in the classifications given, it should be added that the tissues around them are affected by scars, which are especially pronounced in syphilis and often lead to cicatricial deformation of the entire soft palate. In some cases, there is a complete or partial fusion of the soft palate with the back and side walls of the nasal part of the pharynx, in which patients complain of a nasal voice, the impossibility of nasal breathing and the accumulation of nasal mucus, which can neither be removed outward nor drawn into the esophagus.

Classification of defects and deformations of the palate

E. N. Samar classifies defects and deformations of the palate remaining after uranoplasty as follows.

By localization:

I. Hard palate:

1. anterior section (including the alveolar process);
2. middle section;
3. posterior section;
4. lateral sections.

II. Border of the hard and soft palate:

1. along the midline;
2. away from the center line.

III. Soft palate:

1. defects (1 - along the midline, 2 - away from the midline, 3 - tongue);
2. deformations (1 - shortening, 2 - cicatricially altered palate).

IV. Combined.

By size:

1. Small (up to 1 cm).
2. Medium (up to 2 cm).
3. Large (over 2 cm).

By form:

1. Round.
2. Oval.
3. Cleft.
4. Irregular shape.

By shape, we divide through defects into crevice, round, oval and irregular; by size - into small (up to 1 cm in diameter or in length, if the defect is crevice), medium (from 1 to 2 cm) and large (over 2 cm in diameter or in length).

A detailed classification of palate defects that arise after gunshot wounds, inflammations and oncological operations was developed by E. A. Kolesnikov.

According to localization, he distinguishes defects of the anterior, posterior sections and the area of the border of the hard and soft palate; they can be unilateral or bilateral.

Based on the condition of the alveolar process and the location of the defect in it:

1. without alveolar process defect;
2. with a defect of the process (through or non-through);
3. with a defect in the anterior process;
4. with a defect in the lateral process.

Depending on the preservation of the supporting teeth on the upper jaw:

1. defects in the presence of teeth (on one side; on both sides; in different sections, 1-2 teeth);
2. defects in the complete absence of teeth.

By the condition of the surrounding tissues:

1. without cicatricial changes in soft tissues near the defect;
2. with cicatricial changes (of the mucous membrane of the palate, with defects of the soft tissues of the perioral region).

By defect size:

1. small (up to 1 cm);
2. medium (from 1 to 2 cm);
3. large (2 cm and more).

By form:

1. oval;
2. rounded;
3. unspecified defects.

V. I. Zausaev divides all extensive gunshot defects of the hard palate that cannot be closed with local tissues into three groups:

1. defects of the hard palate and alveolar process measuring no more than 3.5x5 cm;
2. more extensive defects of the hard palate and alveolar process;
3. defects of the hard palate and alveolar process, combined with a defect of the upper lip or cheek.

With regard to defects of traumatic origin, we adhere to the above classification of V. I. Zausaev.

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Complications of defects and deformations of the palate

During operations in the anterior and posterior sections of the hard palate, intense bleeding from the greater palatine artery may occur. It can be stopped by temporary pressure or by inserting the end of a closed hemostatic clamp into the bone opening, and then a piece of the spongy part of the allograft or catgut.

When the mucoperiosteal flaps are cut out roughly, a rupture of the mucous membrane of the nasal cavity and opening of the previously corrected non-union of the hard palate may occur.

If the operation is performed under local anesthesia, aspiration of blood clots is possible. To prevent such complications, it is necessary to carefully suck out the contents of the mouth with an electric suction.

After the operation, some difficulty in breathing may sometimes be observed due to changes in breathing conditions, swelling of the mucous membrane of the nose, nasal part of the pharynx, pharynx and trachea (if the operation was performed under eschutracheal anesthesia), and also due to displacement of the tampon from under the plate. Bleeding from the lateral wounds may occur, which is associated with the lysis of thrombi in the vessels damaged during the operation.

If the choice of the surgical method is unsuccessful, there may be a divergence of the sutures, especially after operations using the methods of Axhausen, V. A. Aronson, N. M. Mikhelson. In such cases, as a rule, a repeated operation is inevitable if the defect on the palate is not covered by the resulting scars.

Outcomes and long-term results

Outcomes and remote results depend on the location and size of the defect, postoperative care, speech therapy training, palate massage, etc. If the speech disorder was associated only with air penetration through the defect and it was eliminated surgically, speech normalization occurs several days after the stitches are removed and the edema disappears. In this regard, accidentally occurring traumatic defects of the hard palate in adults are the most promising. The situation is worse with defects and deformations of the soft palate that arose in a child after uranostaphyloplasty: speech normalization in them occurs more slowly, speech therapy training, palate massage, exercise therapy, electrical stimulation, etc. are required.

Unfavorable outcomes are observed in many patients after Schenborn-Rosental operations (lengthening of the soft palate by means of a pharyngeal flap on a pedicle): the flap shrinks, as a result of which the speech remains nasal. This method should be used only in cases where no other method can be used, including suturing of the palatopharyngeal arches (according to A.E. Rauer), after which the results are significantly better than after the Schenborn-Rosental operation.

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Treatment of defects and deformations of the palate

Treatment of acquired defects and deformations of the palate is surgical or orthopedic. The only indication for orthopedic treatment is poor health and a severe general condition of the patient, which does not allow for surgery, especially a multi-stage and complex one.

If the general condition of the patient with a deformed (after uranoplasty) upper jaw is satisfactory, the surgical-orthopedic method of treating upper jaw constrictions developed by E. D. Babov (1992) can be used: after osteotomy of the maxillary counterforces, the midface is widened using an orthodontic device applied on the day of surgery. Osteotomy of the zygomatic arches is performed by the author using the method of G. I. Semenchenko et al. (1987), which consists of transverse osteotomy of the zygomatic arches in the area of the temporozygomatic sutures.

The palate defect should be closed by means of a one-stage local plastic surgery. Only if it is impossible to eliminate the defect in this way should plastic surgery with a Filatov stem be used.

The doctor's tactics for eliminating defects and deformations remaining after unsuccessful uranostaphyloplasty depend on the location, size, shape of the defect, condition and amount of surrounding tissue.

There is no standard method for eliminating all defects, if only because the condition of the surrounding tissues, even around a defect of the same localization, may be different in different patients. For example, even tissues of different parts of the palate that are not changed by scars are very different in the same patient. Thus, in the anterior part of the hard palate there is no submucous tissue at all; on average, it is only around the alveolar processes, but in insignificant quantities; the border of the hard and soft palate is characterized by pronounced tension of the soft tissues. Defects of the soft palate can be combined with its cicatricial shortening, and sometimes with the absence of the uvula or with its inversion into the nasal part of the pharynx.

In this regard, there are 7 sections in the palate: the anterior section, limited by a line from 31 to 13 teeth; two lateral sections, about 543| and |345 teeth; the middle section (4) - between the lateral, anterior and posterior sections, limited in front by a line between 6| and |6 teeth, and in the back by a line from 8| to |8 teeth, broken at an obtuse angle; the "border" section - between this broken line and the line connecting the middles of the crowns of 8_18 teeth; the soft palate.

Methods for eliminating defects of the anterior part of the hard palate and alveolar process, as well as insufficiency of the soft palate

In case of residual non-union of the alveolar process, if there is a gap of 1-3 mm between the edges of non-union, it is recommended to use the method of P. P. Lvov, which consists of the following. Along the edges of non-union, mucoperiosteal flaps of the gum (on a pedicle) are formed, separated and sutured together along the lower edge, and then sutured to the soft tissues of the hard palate and vestibule of the mouth.

If the edges of the fissure defect of the gum are tightly adjacent to each other, they should be de-epithelialized with a fissure bur and, having mobilized the tissue with incisions near the edges of the defect, sutured, as in primary uranoplasty.

Method of D. I. Zimont

If the defect of the anterior palate is small or medium in size, especially if it is slit-shaped, it is best to use D. I. Zimont's method (Fig. 169). The edges of the defect are excised with a narrow and sharp scalpel, an arcuate incision is made to the bone near the papillae of the 4321|1234 teeth and the mucoperiosteal flap is separated with the base facing the middle part of the palate. The edges of the defect are sutured with catgut from the side of the nose, the flap is put in place and the edges of the wound are sutured from the side of the mucous membrane of the palate. Considering that the method does not provide for the creation of a nasal epithelial lining, E. N. Samar proposed to create it using a split autodermal graft, sutured to the edges of the periosteal defect with 4 catgut sutures.

Methods of E. N. Samara

1. In case of defects in the anterior palate, combined with absence of incisors or premaxillary bone, an M-shaped incision is made similar to Langenbeck's incision to form a wide flap from the mucous membrane and periosteum of the entire anterior palate with a pedicle in the middle section (Fig. 170), it is separated, deflected downwards and its ends are sutured; the flap cut from the lip and alveolar process (with a pedicle at the anterior edge of the defect) is turned over with the epithelial surface towards the defect and sutured to the wound surface of the turned back M-shaped mucoperiosteal flap. The formed duplication is placed on the defect of the hard palate and fixed with sutures. The wound on the lip is sutured. The flap should be cut out in the mucosal-submucous layer; in cases where there is an edentulous alveolar process, the continuation of the labial flap is its mucous membrane and periosteum.

To create a duplicate without tension in the seams, the length of this flap should exceed the length of the defect by 1.5-2 cm.

2. In case of defects of the anterior part of the hard palate, combined with two defects of the alveolar process (on the sides of the premaxillary bone), a T-shaped incision is made on the premaxillary bone, with the base facing the teeth; two triangular mucoperiosteal flaps are separated and inverted by 180° to form an internal lining. Langenbeck incisions are made (up to 6 | 6 teeth) and connected at the lower edge of the defects. The separated mucoperiosteal palatal flap is placed on the inverted triangular flaps and fixed with sutures.

When creating a palatal flap according to Langenbeck, it is necessary to separate it very carefully in the middle part so as not to open the bone-mucous defect previously eliminated by the surgeon (during uranoplasty).

Methods for eliminating defects of the anterior and middle parts of the palate

Spanier-Kriemer-PH Chekhovsky Method

The Spanier-Kriemer-PH method of Chekhovsky is applicable in cases where the through defect of the hard palate has an oval shape and does not exceed 1x0.5 cm. In this case, if the tissue reserve allows, the borders of the mucoperiosteal flap are marked and outlined with brilliant green on one of the lateral sides of the defect so that after cutting, separating and turning by 180° it can cover the defect with an excess of 3-4 mm along the perimeter. This peripheral strip of the flap is subjected to deepithelialization using a milling cutter; only the part that is capable of repeating the shape and size of the defect and closing its entire lumen after turning the flap by 180° remains undeepithelialized.

On the opposite side, as well as above and below the defect, an intertissue niche is formed by horizontally stratifying the soft tissues. The depth of the niche should be 4-5 mm.

Then, a mucoperiosteal flap is cut out, separated from the bone base, turned over with the epithelium into the nasal cavity, and the de-epithelialized edge of the flap is inserted into the intertissue niche and fixed with several U-shaped sutures made of polyamide thread, which are tied near the base of the alveolar process. In case of insufficiently tight adhesion of the edge of the intertissue niche (from the side of the oral cavity) to the wound surface of the turned over flap, they should be brought together by applying 1-2 knotted catgut sutures.

If the defect of the hard palate is small (no more than 1 cm in diameter or length), the operation is finished. The wound is closed with an iodoform tampon, reinforced with a protective palatal plate made before the operation. After 3-4 days, the tampon and plate are removed, the wound is irrigated with a solution of hydrogen peroxide and is then treated openly. U-shaped sutures are removed on the 9th-10th day. The wound surface of the flap turned 180° is epithelialized from the edges.

If the size of the through defect of the hard palate exceeds 1 cm, then during the operation, a split skin flap is applied to the wound surface of the flap facing the oral cavity, which is usually prepared on the anterior abdominal wall.

After this, the area of the operation on the palate is covered with a foam plate soaked in deoxycorticosterone acetate, and 2-3 layers of iodoform gauze and a protective plate are applied on top of it.

The first dressing and removal of sutures is done on the 10th day, when the wound surface is already covered with islands of epithelium. The split flap itself, which served as the source of epithelialization, never completely takes root. Its non-taken edges must be carefully cut off and removed. By this time, the marginal epithelialization of the wound surface is also noticeable. In the future, the wound is treated openly.

If the defect of the hard palate is triangular and so large that it cannot be covered with one flap, a two-flap method should be used - turning over and suturing two flaps cut along the edges of the defect. Some of the edges of such flaps, turned over by the epithelium into the nasal cavity, must inevitably end up in the intertissue niches (above and below the place where the flaps were cut out). Therefore, the area of free overlap of two flaps (i.e. their mutual overlap), as well as the edges to be introduced into the intertissue niches, must be subjected to deepithelialization with a burr. The non-deepithelialized areas on both flaps, when folded, must correspond to the area of the through defect. After cutting, separating from the bone and turning over by 180°, the flaps are sutured together with U-shaped sutures. The edges of the flaps inserted into the intertissue niches are fixed with the same sutures. For more reliable and rapid epithelialization, the wound surface of the inverted flaps can be covered with a split skin flap.

In order to eliminate extensive through defects of the anterior section of the hard palate remaining after surgery for bilateral nonunion of the palate and alveolar process, R. N. Chekhovsky also recommends using the above-described method of inverting two flaps from the sides of the defect. But to cover them, the author uses a mucoperiosteal flap cut on the vomer and premaxillary bone; its pedicle faces forward - toward the incisive opening on the premaxillary bone. The flap is lifted from its base and placed on the inverted and sutured lateral flaps.

To eliminate residual defects in the anterior section of the hard palate, E. N. Samar recommends using the method of D. I. Zimont. To eliminate small and medium defects in the area of the hard palate, E. N. Samar and Burian use two flaps: one is tilted into the nose (with a pedicle at the edge of the defect), and the second is shifted from the adjacent section of the palate (on a pedicle facing the vascular bundle). The first flap is formed on one side of the defect, the second on the opposite side.

The use of this method is based on the assumption that the tissues bordering the defect are in a state of chronic inflammation and therefore their regenerative capacity is reduced. We do not share these concerns; the experience of our clinic shows the high viability of flaps cut at the edge of the defect and turned 180° by the epithelium into the nasal cavity, which is also confirmed by experimental studies.

The method of Y. I. Vernadsky

To eliminate a large polygonal defect of the hard palate, we can recommend a local plastic method of closing it, conventionally called by us "multi-flap", which allows us to avoid the use of multi-stage plastic surgery with a Filatov stem. According to each defect facet, a de-epithelialized mucoperiosteal flap is cut out and turned over (on a pedicle facing the defect edge). As a result of the mutual overlap of several (3-4-5) flaps, the entire defect is completely closed. To increase the viability of the flaps, the likelihood of their "sticking" to each other and "survival", we recommend that the patient perform a finger massage of the defect edges for 2-3 preoperative days.

If the defect of the hard palate is very large, it is not always possible to eliminate it the first time, even when using a multi-flap technique. In such cases, the operation has to be repeated using the same technique every 2-3 months, achieving a gradual reduction in the size of the defect each time until it is completely eliminated. Experience shows that 2-3-fold surgery is tolerated by patients much easier than multi-stage plastic surgery using a Filatov stem.

A. E. Rauer's method

To eliminate postoperative through and combined defects of the soft palate, shortening (insufficiency) and cicatricial deformation of the soft palate, many surgeons resort to repeated radical uranostaphyloplasty.

In case of cicatricial changes in the anterior sections of the hard palate and shortening of the soft palate to 2 cm, E. N. Samar recommends the A. E. Rauer operation - suturing of the palatopharyngeal arches. In our clinic, this operation is used very rarely.

As for the Schenborn-Rosental operation (plastic surgery of the soft palate with a flap on a pedicle from the back wall of the pharynx), we do not use it at all, considering it non-physiological (it creates unavoidable conditions for closed nasal speech), and in terms of consequences - unhygienic due to the constant disruption of normal ventilation of the nasal part of the pharynx.

Method of G. V. Kruchinsky

Of great practical interest is the proposal to eliminate defects in the area of the hard palate (including those extending to the alveolar process) or the border of the hard and soft palate using a pedicled flap from the tongue according to Vuerrero - Santos. G. V. Kruchinsky improved this method and considers it suitable for eliminating defects ranging in size from 1x1.5 to 1.5x2 cm. The operation according to G. V. Kruchinsky's method is performed under intratracheal anesthesia. The lining from the side of the nasal cavity is restored by turning over mucoperiosteal flaps from the edges of the defect. Then a flap is cut out in the area of the back of the tongue, starting in front of the blind opening; its pedicle should be located in the area of the tip of the tongue. The flap of the mucous membrane together with a layer of longitudinal muscles of the tongue is separated almost to the tip of the tongue; gradually suturing the edges of the wound, the flap is converted into a tube. The flap formed in this way is a continuation of the tongue and has a powerful nutritional stalk.

At the end of the operation, the tongue is fixed with two mattress sutures (on rubber tubes) to the small molars of the upper jaw. The flap is sutured to the edges of the wound in the area of the palate defect. The tongue is pulled up and fixed by tying the previously prepared mattress sutures on both sides.

After 14-16 days, the stalk is cut off from the tongue, finally spread out on the wound of the palate, and part of the stalk is returned to its original place. The author believes that the nutritive stalk can be formed not only at the tip, but also at the root of the tongue or its lateral surface.

In conclusion of the consideration of the issue of plastic surgery for residual defects of the hard palate after previously performed uranoplasty, it should be noted that lyophilized dura mater, which has proven to be a promising plastic material, is successfully used to replace the bone tissue defect.

Surgical restoration of the function of the velopharyngeal sphincter in patients previously subjected to uranostaphyloplasty

Methods of E. N. Samara and N. A. Miroshnichenko

Using X-ray tomographic and spectral methods of speech analysis of patients before and after uranostaphyloplasty, developed by E. N. Samar (1986), N. A. Miroshnichenko (1991) established the need for correction of the velopharyngeal sphincter in 120 patients.

If this was caused by a pronounced atrophy of the palatopharyngeal muscles and the superior pharyngeal constrictor, correction was performed using the following technique (E. N. Samar, N. A. Miroshnichenko, 1984, certificate of authorship #1524876): the lower sections of the medial pterygoid muscles on the inner surface of the lower jaw were isolated from incisions along the pterygomaxillary folds on both sides, after which the medial bundles of these muscles up to 2.0 cm wide were cut off from the lower edge of the angles of the lower jaw. The prepared bundles of muscles were introduced into the area of the lower part of the soft palate and sutured together along the midline with catgut.

The results of functional studies of the palatopharyngeal sphincter showed that there are prerequisites for reconstructing the palatopharyngeal sphincter after primary plasty of the palate not by retrotransposition of the soft palate, but by bringing the muscles of the superior pharyngeal constrictor closer to it. A total of 54 patients were operated on using this technique. Of these, 20 were aged 5 to 9 years; 19 were aged 10 to 13 years; 16 were over 13 years old; X-ray tomographic examination of the palatopharyngeal sphincter was performed before the operation.

In patients with submucous nonunions of the palate, insufficiency of the velopharyngeal closure was noted on X-ray tomograms; their surgical treatment was performed with mandatory retrotransposition of the soft palate or with reconstruction of the velopharyngeal sphincter. Therefore, 11 patients with a submucous defect of the palate underwent surgery according to Waugh-Kilner, and 4 patients - according to the method of these authors: when cutting out mucoperiosteal flaps on the hard palate, the vascular-nerve bundle was dissected on one side to the middle section, after which the anterior third of the flap on an arterial pedicle was moved into a diamond-shaped defect of the nasal mucosa at the border of the hard and soft palate, made for retrotransposition.

The rest of the nasal mucosa remained intact. After that, the soft palate muscles, mucous membranes, and mucoperiosteal flaps were sutured layer by layer. In all 15 patients, the anatomical result of the operation was positive, while the functional result was good in 9 people; in the remaining 6, speech improved, but did not reach the norm. The authors note that even with complete restoration of the palate tissue, the functional activity of the palatopharyngeal sphincter is not always observed.