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                                                       Microsurgery
A therapeutic revolution has taken place in gen-       cation, has become an integral part of modern               Three types of keplerian loupes are common-
eral surgery requiring the retraining of thousands     dental practices.                                      ly employed in dentistry: simple single-element
of surgeons and the retooling of their operating                                                              loupes (Figures 29-3 and 29-4), compound loupes
rooms. This change has come about owing to the                                                                (Figures 29-5 and 29-6), and prism telescopic
                                                       Magnification Systems
acceptance of microscopic surgery in many areas                                                               loupes (Figures 29-7 and 29-8). Each type may dif-
of medicine, such as vascular, corneal, otologic,      A variety of simple and complex magnification          fer widely in optical sophistication and individual
neurologic, gynecologic, and, in particular, laparo-   systems are available to practitioners, ranging        construction (Table 29-1). For most periodontal
scopic and arthroscopic procedures.                    from simple loupes to prism telescopic loupes          procedures performed using loupe magnification
      These procedures were a natural evolution of     and, ultimately, to the surgical microscope. Each      for increased preciseness, either compound or
microsurgical advances and have become accept-         magnification system has specific advantages and       prism loupes, of ×4 to ×5 magnification, are used
ed as routine by the general public. Over the past     limitations. When selecting which mode of mag-         to provide the most effective combination of mag-
decade, the field of periodontics has seen increas-    nification should be used for improved visual          nification, field size, and depth of focus.
ing surgical refinement of many procedures. Such       acuity, the task at hand must be considered. The
refinements require more detailed surgical skills      assumption that more magnification is better           Simple Loupes
resulting from increased visual acuity. Consistent     must be weighed against the decrease in field of       Simple loupes consist of a pair of single, positive,
successful guided tissue regeneration, cosmetic        view and depth of focus that occurs as magnifica-      side-by-side menicus lenses (see Figure 29-4).
crown lengthening, gingival augmentation pro-          tion increases (Figure 29-1). Therefore, an under-     Such loupes are primitive magnifiers, with limit-
cedures, soft and hard tissue ridge augmentation,      standing of the optical principles that govern         ed capabilities. Each lens has two refracting sur-
osseous resection, and dental implants demand          magnification is essential to the successful use of    faces, with one occurring as light enters the lens
clinical expertise that challenges the technical       magnification in the clinical practice of dentistry.   and the other when it leaves. The magnification
skills of periodontists to the limits of and beyond    Microdentistry and periodontal microsurgery are        of simple loupes can be increased only by aug-
the range of normal visual acuity.                     acquired skills, requiring magnification, micro-       menting the lens diameter or thickness. Because
      Periodontal microsurgery has thus evolved.       surgical instruments, intensive training, and fre-     of their size and weight limitations, they have no
Periodontal microsurgery is not a specific opera-      quent practice to achieve and maintain excellence.     practical dental application beyond a magnifica-
tion intended to replace traditional periodontal                                                              tion range of 1.5 diameters, where working dis-
surgery but a methodology that improves all            Magnifying Loupes                                      tances and depths of field are compromised.
aspects of surgical techniques. “Microsurgery” is      Surgical loupes are the most common system of
defined as refinements in existing basic surgical      optical magnification used in dentistry. Funda-        Compound Loupes
techniques that are made possible by the use of the    mentally, loupes are two monocular microscopes         Compound loupes (see Figure 29-6) are converg-
surgical microscope with subsequent, significant       with side-by-side lenses converging to focus on        ing multiple lenses with intervening air spaces to
improved visual acuity. Traditional “macroscopic       the operative field. The magnified image is            gain additional refracting power, magnification,
surgery” or “macrosurgery” is defined as those sur-    formed with stereoscopic properties by virtue of       working distance, and depth of field. They are
gical procedures performed with the unaided eye,       the convergent lenses. A convergent lens system is     also “achromatic” (color correct), which is highly
without the assistance of magnification.               called a keplerian optical system (Figure 29-2).       desirable. Size and weight are not significant
      Owing to the “visual advantage” gained with
microsurgery, macrosurgery and microsurgery are
not comparable. In macrosurgery, hand move-                                                                                                       Eye
ments are guided proprioceptively, whereas in
microsurgery, they are guided visually. These visu-                                                                                               Lenses of
                                                                                                                                                  eye piece
ally guided movements not only position the hands
for the execution of prelearned movements but
also through their entire range of motion, with
visual feedback and midcourse corrections. Visual-
                                                                                                                                                  Binocular
ly guided movements result in greater accuracy of                                                                                                 objectives
hand movements, which are retrained with use and
practice. Microscopically visually guided move-
ments allow the periodontist to achieve clinical
results once thought unlikely on a consistent basis.
      Optical magnification has, therefore, broad-                                                                                                Object
ened the horizons of dentistry in general and
periodontics in particular. Improvement in visu-       FIGURE 29-1 Magnifications (clockwise from upper             FIGURE 29-2 Keplerian optics.
al acuity, made possible through optical magnifi-      left) 2×, 4×, 8×, and 16×.
434 Advanced Surgical Procedures




FIGURE 29-3 Simple loupes.                                            FIGURE 29-4 Simple loupe optical diagram.                          FIGURE 29-5 Compound loupes.




FIGURE 29-6 Compound loupe optical diagram.                           FIGURE 29-7 Eyeglass-mounted prism loupes.                         FIGURE 29-8 Prism loupe optical diagram.



problems for the ×4 to ×5 magnification com-                          Operating Microscope                                               should also incorporate fully coated optics and
monly used in periodontics.                                           The surgical operating microscope is much more                     achromatic lenses, with high resolution and good
                                                                      versatile and advantageous than magnifying                         contrast stereoscopic vision.
Prism Loupes                                                          loupes (Table 29-2). The microscope offers mul-
Prism loupes are the most optically advanced                          tiple flexibility in magnification optics and com-                 Maneuverability
type of loupe magnification presently available                       fort (Figure 29-9). Operating microscopes suit-
(see Figure 29-8). Prism loupes contain Schmidt                       able for use in periodontics use galilean optical                  For practical use in periodontics, a surgical micro-
or rooftop prisms, which lengthen the light path                      principles (Figure 29-10).                                         scope must have maneuverability, stability, and an
through a series of mirror reflections within the                          Such scopes use the application of the mag-                   adequate working distance for instrumentation.
loupes, virtually folding the light so that the bar-                  nifying loupe in combination with a magnifica-                     Microscope mountings play an important role in
rel of the loupe can be shortened. Only the surgi-                    tion changer and a binocular viewing system so                     maneuverability and scope stability and are avail-
cal microscope can provide better magnification                       that the scopes employ parallel binoculars for                     able for the ceiling, the wall, or a floor stand.
and optical characteristics than prism loupes.                        protection against eye strain and fatigue. They                         Maneuverability must always be sufficient to
                                                                                                                                         meet the requirements of clinicians for increased
                                                                                                                                         visual accessibility to the various anatomic struc-
  Table 29-1 Keplerian Loupes                                                                                                            tures dealt with in periodontics. Inclinable eye-
                                                                                                                                         pieces are an indispensable necessity for the
                                Maximum Usable
  Type               Lens        Magnification                      Advantages                           Disadvantages*                  maneuverability and flexibility necessary for the
                                                                                                                                         clinical use of the surgical microscope in peri-
  Simple           Single               1.5 ×            Simplicity                             Spherical (shape) and                    odontics. Because the optical characteristics of
                                                                                                  chromatic (color) distortions          most manufacturers’ lenses are comparable,
                                                                                                  with increased size and
                                                                                                                                         microscope maneuverability is often more
                                                                                                  weight increased
                                                                                                                                         important than optical characteristics in deter-
                                                                                                  magnifications
                                                                                                                                         mining the appropriate microscope for peri-
  Compound         Multiple             3.0 ×            Increased magnification                Limited depth of field
                                                                                                                                         odontal procedures (Figures 29-11 and 29-12).
                                                                                                Limited field access
  Prism            Multiple             4.0 ×            Higher magnification                   Increased weight above 4×
                                                         Wide depth of field                                                             Illumination
                                                         Longer working distances
                                                         Larger fields of view                                                           Illumination of the field is an important consid-
                                                                                                                                         eration. Periodontists are accustomed to lateral
  *A major disadvantage of the design of keplerian loupes is that the clinician’s eyes must converge to view the operative field. This
    can result in eye strain, fatigue, and even vision changes, especially after prolonged use of poorly fitted loupes.                  illumination from side-mounted dental lights.
                                                                                                                                         Clinicians who work with loupes often require a
                                                                                                                                              Microsurgery      435

  Table 29-2 Operating Microscope

                          Maximum Usable
  Type            Lens     Magnification                Advantages                      Disadvantages
  Microscopic Multiple          4–20×         Binocular eyepieces                 Fixed positioning of patient
                                              Parallel optical eyepieces permit   High initial setup costs
                                                relaxed stereoscopic viewing      Limited site use to 60–80%
                                              Achromatic (color stable)
                                                lenses
                                              High resolution
                                              Efficient illumination
                                              Increased depth of field
                                              Increased field of view                                            FIGURE 29-12 Periodontal operatory equipped for
                                              Ability to easily change                                           microsurgery.
                                                magnification

                                                                                                                 procedures of all types: either 35 mm slides or dig-
                                                                                                                 ital photographs can be easily produced using a
headlamp to compensate for the decreased                 Documentation                                           beam splitter camera attachment (Figure 29-13).
amount of light passing through the loupes.
                                                         Documentation of periodontal procedures has             With a foot-operated shutter control, the surgeon
Until recently, coaxial fiber optic illumination
                                                         become increasingly important for both dental-          can compose the photographic field as the proce-
had been a major advantage of the operating
                                                         legal reasons and for patient and professional edu-     dure unfolds without interrupting the surgical
microscope over surgical loupes. Coaxial lighting
                                                         cation purposes. The surgical operating micro-          process for photography. An advantage of micro-
places the light source parallel to the optical axis
                                                         scope is ideal for documenting periodontal              scopic photography is that it represents the surgi-
via a prism beam splitter. With coaxial lighting,
                                                                                                                 cal field exactly as the surgeon sees it as opposed to
no shadows are produced, and the clinician can
                                                                                                                 a photographer’s view produced from a different
better view into the farthest reaches of the oral
                                                                                                                 angle while the surgeon works. Excellent video
cavity, including into some subgingival pockets                                                Eye               documentation is also available through the oper-
and angular defects. Improved visualization of
                                                                                                                 ating microscope using a video beam splitter
root surface irregularities and deposits is pos-                                               Lenses of
                                                                                               eye piece
                                                                                                                 attachment. High-resolution digital cameras with
sible. The clinician is often able to view aspects of
                                                                                                                 video and slide printers are currently replacing
both normal and abnormal periodontal anatomy
                                                                                                                 35 mm camera photography in many microsurgi-
never previously accessible. Clinical decisions
                                                                                                                 cal disciplines. High-resolution S-VHS recorders
can be made based on improved visual knowl-                                                    Prism
                                                                                               assembly          bring new capabilities for video recording of peri-
edge of altered anatomy rather than educated
                                                                                                                 odontal procedures for educational purposes.
guesses. Coaxial lighting has also become avail-                                               Binocular
able in prism telescopic loupes.                                                               objectives
                                                                                                                 Periodontal Microsurgery
                                                                                                                 In recent years, periodontics has witnessed
                                                                                                                 increasing refinement and consistency of proce-
                                                                                                                 dures, requiring progressively more intricate sur-
                                                                                               Object
                                                                                                                 gical skills. Regenerative and resective osseous
                                                         FIGURE 29-10 Galilean optics microscope diagram.        surgery, periodontal plastic surgery, and dental
                                                                                                                 implants demand clinical performance that chal-
                                                                                                                 lenges the technical skills of periodontists beyond
                                                                                                                 the range of ordinary visual acuity.




FIGURE 29-9 Operating microscope.                        FIGURE 29-11 Microscope on a rotating mount.            FIGURE 29-13 Microscope camera and beam splitter.
436 Advanced Surgical Procedures

     Periodontal microsurgery introduces the                                                              Conclusions
possibility for considerably less invasive surgical
procedures in periodontics, exemplified by small-                                                         Viewing periodontal surgery under magnification
er, more precise surgical incisions for access and,                                                       cannot help but impress the clinician with the
consequently, less need for vertical releasing inci-                                                      coarseness of conventional surgical manipulation.
sions. Periodontists, like other microsurgeons,                                                           What appears to the unaided eye as gentle han-
have been surprised by the extent to which                                                                dling is revealed, under magnification, as gross
reduced incision size is directly related to reduced                                                      crushing and tearing of delicate tissues. Periodon-
postoperative patient pain.
                                                        FIGURE 29-14 Microsurgical instruments.
Advantages
1.    Less tissue trauma
2.    Less mobility
3.    Less patient anxiety
4.    Atraumatic tissue management
5.    Accurate primary wound closure
6.    Increased diagnostic skills
7.    Minimally invasive
8.    Improved cosmetic results
9.    Increased surgical quality                                                                           A
10.   Increased effectiveness of root débridement       FIGURE 29-15 Castroviejo microsurgical scalpel.
      results in greater predictability of
      a. Regeneration procedures
      b. Cosmetic procedures
      Improved documentation
      a. Video
      b. Slide
      c. Digital

Disadvantages
1.    Educational requirements
      a. Surgical technique                                                                                B
      b. Understanding of optics
2.    Long adjustment period for clinical profi-
      ciency
3.    Initial increased surgical time
4.    Higher patient cost
5.    Limited surgical access

Microsurgical Instruments
In addition to the use of magnification and
reliance on atraumatic technique, microsurgery
entails the use of specially constructed microsur-                                                         C
gical instruments specifically designed to mini-
                                                        FIGURE 29-16 Microsutures and microinstruments
mize trauma (Figures 29-14 and 29-15). An
                                                        at ×10 magnification.
important characteristic of microsurgical instru-
ments is their ability to create clean incisions to
prepare the wound for healing by primary inten-
tion. Such incisions are established at 90° angles to
the surface using a Castroviejo microsurgical
scalpel (Figure 29-16). Magnification permits easy
identification of ragged wound edges for trim-
ming and freshening. To permit primary wound
closure, microsutures in the range of 6-0 to 9-0
(Figure 29-17) with microsurgical needle holders                                                           D
are required to correctly approximate the wound
                                                                                                          FIGURE 29-18 A, Suture practice on latex at ×8 mag-
edges (Figure 29-18). Microsurgical wound appo-
                                                                                                          nification. B, Suture practice on latex at ×24 magnifi-
sition minimizes gaps or voids at the wound                                                               cation. C, Suture practice on latex at ×32 magnifica-
edges, which encourages rapid healing, with less                                                          tion. D, Suture practice on foliage (anthurium flower)
postoperative inflammation and less pain.               FIGURE 29-17 Sutures in human hair.               at ×32 magnification.
                                                                                                                 Microsurgery   437

tists have attempted to treat the surgical site atrau-        Periodontal surgery is a natural extension of
matically to achieve primary wound closure.              conventional surgical principles by which magni-
However, the limits of normal vision dictate the         fication is employed to permit accurate and
extent to which this goal is possible. For surgeons      atraumatic handling of soft and hard tissues to
who perform periodontal surgery to continue to           enhance wound healing.
live up to their reputation of being experts in deft-         Figures 29-19 to 29-21 illustrate periodon-
ly handling soft and hard tissues, proficiency in        tal surgery cases treated using microsurgical
periodontal microsurgery is a necessity.                 techniques.




A1                                                       B1




A2                                                       B2




A3                                                       B3

                                                         FIGURE 29-19 A, 1, Deep-wide gingival recession on
                                                         maxillary cuspid. 2, Microsurgical subepithelial con-
                                                         nective tissue graft ×4 magnification. 3, Same case
                                                         viewed at ×20 magnification. 4, Final postoperative
                                                         result. B, 1, Multiple areas of recession (central
                                                         incisor and cuspid). 2, Microsurgical subepithelial
                                                         connective tissue graft sutured with minimal trauma.
                                                         3, One-month postoperative result.



A4
438 Advanced Surgical Procedures




A1                                                         A2                                                         A3




B1                                                         B2                                                         B3
FIGURE 29-20 A, 1, Mucogingival frenum abnormality with slight recession. 2, Subepithelial microsurgery to reposition the frenum and augment attached gingiva with
a connective tissue graft. 3, One-month postoperative result. B, 1, Multiple areas of gingival recession. 2, Mirosurgical subepithelial connective tissue graft with a coro-
nally positioned flap. 3, Final result with 100% root coverage.




A1                                                         A2                                                         A3




B1                                                         B2                                                         B3
FIGURE 29-21 A, 1, Papilla reconstruction prior to surgery. 2, Microsurgical view of papillary reconstruction. 3, Papillary reconstruction completed. B, 1, Significant
recession on the canine tooth. 2, Microsurgical subepithelial connective tissue graft coverage by a double-papilla flap. 3, Complete root coverage with a wide zone of
keratinized gingiva, 3-month result.

				
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