Maxillary furcation-involved class II subclass B molar with advanced distal vertical bone defect treated by Er:YAG laser-assisted comprehensive periodontal pocket therapy under a microscope: A case report

Furcation involvement is one of the most important factors affecting the long-term prognosis of multi-rooted teeth. In particular, maxillary molars with furcation involvement and advanced vertical bone loss are difficult to manage because of their complex root anatomy and limited accessibility for debridement, especially at the distal furcation area. Conventionally, furcation-involved maxillary molars with advanced vertical bone destruction, particularly at the distal furcation area, are considered highly challenging for periodontal regenerative therapy because of their complex root anatomy and limited accessibility for adequate debridement, and extraction may also be considered in severe cases.1 Recently, Er:YAG laser-assisted comprehensive periodontal pocket therapy (Er-LCPT) has demonstrated favorable clinical outcomes as a minimally invasive flapless surgical approach2–4 owing to excellent inflammation suppression and photo-biomodulation (PBM) effect.5 Under microscopic visualization, the delicate sapphire tip of the Er:YAG laser provides excellent accessibility to anatomically restricted areas, allowing effective debridement even within furcation defects. Herein, we presented a maxillary furcation-involved Class II subclass B molar with advanced distal vertical bone destruction successfully treated by minimally invasive Er-LCPT under microscopic visualization.

A 43-year-old female patient was referred to our hospital with the chief complaint of discomfort and pain during mastication at the upper right molar region. Clinical examination revealed bleeding on probing (BOP), suppuration, and deep probing pocket depth (PPDs) at the buccal and distal furcation-involved area of the maxillary right second molar (Fig. 1A and B). The buccal and distal furcation-involved area demonstrated a Class II subclass B defect with advanced vertical bone defect, with mesio-buccal, buccal, and disto-buccal PPDs of 3, 8, and 10 mm, respectively, and mesio-palatal, palatal, and disto-palatal PPDs of 3, 3, and 10 mm, respectively. Following local anesthesia, Er-LCPT under a dental operating microscope was performed without flap elevation according to our previous published study (Fig. 1C), preoperative periapical radiography and cone-beam computed tomography (CBCT) revealed severe vertical bone destruction extending into the furcation area (Fig. 1D–G). At the 1-year follow-up, favorable soft tissue healing was observed without gingival recession (Fig. 1H–J). The mesio-buccal, buccal, and disto-buccal PPDs were reduced to 3, 3, and 3 mm, respectively, and the mesio-palatal, palatal, and disto-palatal PPDs were also reduced to 3, 3, and 3 mm, respectively, without BOP. Periapical radiographic and CBCT examinations demonstrated favorable bone fill around the furcation area compared with the preoperative condition (Fig. 1K–N).

Figure 1.

Maxillary furcation-involved Class II subclass B molar with advanced distal vertical bone defect treated by Er:YAG laser-assisted comprehensive periodontal pocket therapy (Er-LCPT) under a microscope. (A) Before treatment, the maxillary right second molar showed gingival swelling and redness at the buccal and distal furcation-involved area. (B) The buccal and distal furcation-involved area demonstrated a Class II subclass B defect with advanced vertical bone defect associated with bleeding on probing (BOP), with mesio-buccal, buccal, and disto-buccal probing pocket depths (PPDs) of 3, 8, and 10 mm, respectively, and mesio-palatal, palatal, and disto-palatal PPDs of 3, 3, and 10 mm, respectively. (C) The furcation bone defect was treated by Er: YAG laser (Litetouch™, Light Instruments, Yokneam Lllite, Israel) irradiation with a straight sapphire tip with a 400 μm diameter to remove inflamed connective tissue on the inner gingival and bone surfaces in a sweeping motion at approximately 30 mJ/pulse (panel setting: 40 mJ/pulse; energy density: 23.9 J/cm²/pulse) and 20 Hz in contact mode under water spray, followed by thorough debridement using micro mini five curettes and ultrasonic scaler under a microscope. After pocket debridement, the outer epithelium was intentionally removed by Er:YAG laser irradiation to prevent epithelial downgrowth into the periodontal pocket. A blood clot-formation procedure was performed using Er:YAG laser irradiation without water spray under non-contact mode for blood clot stabilization. (D) The preoperative periapical radiograph demonstrated severe vertical bone destruction associated with the furcation area. (E) The preoperative CBCT sagittal view demonstrated advanced vertical bone destruction extending into the furcation area. (F) The preoperative CBCT coronal view revealed severe bone loss involving the furcation area. (G) The preoperative CBCT axial view demonstrated bone destruction within the furcation area. (H–J) At the 1-year follow-up, favorable soft tissue healing and stable periodontal condition were observed without gingival recession or bleeding on probing. (K) The 1-year postoperative periapical radiograph demonstrated favorable bone fill at the furcation defect area. (L–N) The postoperative CBCT views demonstrated favorable bone regeneration and around the furcation area.

The results of the present case suggest that Er-LCPT under a microscope may represent a useful minimally invasive treatment option for maxillary furcation-involved molars with advanced vertical bone destruction, even in anatomically challenging distal furcation areas. In addition, the flapless approach may contribute to preservation of soft tissue architecture and prevention of postoperative gingival recession. Therefore, minimally invasive flapless therapy such as Er-LCPT may represent a potential minimally invasive treatment option before considering conventional open flap regenerative surgery for furcation-involved maxillary molars. Further clinical studies are required to evaluate the long-term predictability of Er-LCPT for maxillary molars with advanced furcation involvement.